ISRO Scientist Syllabus & Exam Pattern 2026: Detailed Guide for Engineers

Mastering the official ISRO Scientist syllabus is a critical step for success in the upcoming recruitment examination. By thoroughly reviewing the topic-wise syllabus and exam pattern, candidates can identify high-weightage areas and streamline their study efforts. To secure a prestigious position as an ISRO Scientist/Engineer, aspirants must excel in a written test covering core engineering technical subjects, arithmetic, and logical reasoning. We have compiled this detailed guide to help you build a strategic and effective preparation schedule.

ISRO Scientist Syllabus and Exam Pattern 2026

The Indian Space Research Organisation (ISRO) has announced 320 vacancies for Scientist/Engineer positions across Mechanical, Computer Science, and Electronics engineering disciplines. Given that technical engineering subjects account for 80% of the examination weightage, it is essential to complete the ISRO Scientist Syllabus 2026 well in advance. The selection process consists of a rigorous written examination followed by a personal interview.

ISRO Scientist Syllabus and Exam Pattern 2026
Conducting Body	Indian Space Research Organisation (ISRO)
Post Name	Scientist Engineer SC Level
Disciplines	Mechanical, Computer Science, and Electronics
Total Questions	95
Total Marks	100
Duration	2 hours
Negative Marking	⅓
Selection Process	Written Exam and Interview
Official Website	www.isro.gov.in

ISRO Scientist Engineer Selection Process

The ISRO Scientist/Engineer recruitment process for 2026 is divided into two primary stages.

• Written Test: This includes questions on Engineering Discipline, Aptitude, and Arithmetic Ability.
• Interview: Candidates who clear the written test will be shortlisted for the interview

Final selection is determined by a combined score, calculated as 50% from the written test and 50% from the performance in the Interview.

ISRO Scientist Exam Pattern 2026

The structure of the ISRO Scientist/Engineer examination is organized as follows:

Part A: Core Technical questions based on your specific engineering branch.

• There are 80 multiple-choice questions
• Each question carries 1 mark
• 1/3 mark deducted for each wrong answer

Part B: General Aptitude and Logical Reasoning.

• There are 15 objective-type questions of 20 marks
• There will be no negative marking

Part	Subjetcs	Questions	Marks	Duration
A	Engineering Discipline	80	80	2 hours
B	Aptitude and Reasoning	15	20
	Total	95	100

Minimum Qualifying Marks
Category	Written Exam (Each Part)	Interview	Aggregate
Unreserved Candidates	50%	50/100	60% overall
Reserved Candidates (PwBD only)	40%	40/100	50% Overall

Allocation of Marks in the Interview
Technical (Academic) Knowledge	40
General Awareness in relevance to the area of specialization (Technical)	20
Presentation/Communication Skills	20
Comprehension	10
Shortlisting Criteria Based on Academic Achievements: Institute type (IITs, IISc, NIT & NIRF top 20) Academic Performance: CGPA ≥ 9 / Percentage > 85% CGPA 7.5 - 9 / Percentage 71 - 85% Other Rank awarded by institute (1 to 3)	10
Total	100

ISRO Scientist Engineer Syllabus 2026

The ISRO Scientist Syllabus covers all critical technical subjects for the written examination. Utilizing this syllabus will help candidates organize their preparation to maximize their scoring potential. Below, we have outlined the core topics for Mechanical, Electronics, and Computer Science Engineering.

ISRO Scientist Mechanical Engineering Syllabus

Materials, Manufacturing, and Industrial Engineering

• Casting, Forming, and Joining Processes: Different types of castings, design of patterns, molds, and cores; solidification and cooling; riser and gating design. Plastic deformation and yield criteria; fundamentals of hot and cold working processes; load estimation for bulk (forging, rolling, extrusion, drawing) and sheet (shearing, deep drawing, bending) metal forming processes; principles of powder metallurgy. Principles of welding, brazing, soldering, and adhesive bonding.
• Machining and Machine Tool Operations: Mechanics of machining; basic machine tools; single and multi-point cutting tools, tool geometry and materials, tool life and wear; economics of machining; principles of non-traditional machining processes; principles of work holding, jigs and fixtures; abrasive machining processes; NC/CNC machines and CNC programming.
• Metrology and Inspection: Limits, fits and tolerances; linear and angular measurements; comparators; interferometry; form and finish measurement; alignment and testing methods; tolerance analysis in manufacturing and assembly; concepts of coordinate-measuring machine (CMM).
• Computer Integrated Manufacturing: Basic concepts of CAD/CAM and their integration tools; additive manufacturing.
• Production Planning and Control: Forecasting models, aggregate production planning, scheduling, materials requirement planning, lean manufacturing.
• Inventory Control: Deterministic models; safety stock inventory control systems.
• Operations Research: Linear programming, simplex method, transportation, assignment, network flow models, simple queuing models, PERT, and CPM
• Engineering Materials: Structure and properties of engineering materials, phase diagrams, heat treatment, and stress-strain diagrams for engineering materials.

Applied Mechanics and Design

• Theory of Machines: Displacement, velocity, and acceleration analysis of plane mechanisms; dynamic analysis of linkages, cams, gears, and gear trains, flywheels and governors; balancing of reciprocating and rotating masses; gyroscope.
• Vibrations: Free and forced vibration of single-degree-of-freedom systems, the effect of damping, vibration isolation, resonance, and critical speeds of shafts.
• Machine Design: Design for static and dynamic loading; failure theories; fatigue strength and the S-N diagram; principles of the design of machine elements such as bolted, riveted, and welded joints; shafts, gears, rolling and sliding contact bearings, brakes, and clutches, springs.
• Engineering Mechanics: Free-body diagrams and equilibrium; friction and its applications including rolling friction, belt-pulley, brakes, clutches, screw jack, wedge, vehicles, etc.; trusses and frames; virtual work; kinematics and dynamics of rigid bodies in plane motion; impulse and momentum (linear and angular) and energy formulations; Lagrange’s equation.
• Mechanics of Materials: Stress and strain, elastic constants, Poisson’s ratio; Mohr’s circle for plane stress and plane strain; thin cylinders; shear force and bending moment diagrams; bending and shear stresses; the concept of shear center; deflection of beams; torsion of circular shafts; Euler’s theory of columns; energy methods; thermal stresses; strain gauges and rosettes; testing of materials with the universal testing machine; testing of hardness and impact strength.

Fluid Mechanics and Thermal Sciences

• Thermodynamics: Thermodynamic systems and processes; properties of pure substances, the behavior of ideal and real gases; zeroth and first laws of thermodynamics, calculation of work and heat in various processes; second law of thermodynamics; thermodynamic property charts and tables, availability and irreversibility; thermodynamic relations.
• Applications: Power Engineering: Air and gas compressors; vapor and gas power cycles, concepts of regeneration and reheat. I.C. Engines: Air-standard Otto, Diesel, and dual cycles. Refrigeration and air-conditioning: Vapor and gas refrigeration and heat pump cycles; properties of moist air, psychrometric chart, basic psychrometric processes. Turbomachinery: Impulse and reaction principles, velocity diagrams, Pelton-wheel, Francis and Kaplan turbines; steam and gas turbines.
• Fluid Mechanics: Fluid properties; fluid statics, forces on submerged bodies, stability of floating bodies; control-volume analysis of mass, momentum, and energy; fluid acceleration; differential equations of continuity and momentum; Bernoulli’s equation; dimensional analysis; the viscous flow of incompressible fluids, boundary layer, elementary turbulent flow, flow through pipes, head losses in pipes, bends, and fittings; basics of compressible fluid flow.
• Heat-Transfer: Modes of heat transfer; one-dimensional heat conduction, resistance concept and electrical analogy, heat transfer through fins; unsteady heat conduction, lumped parameter system, Heisler’s charts; thermal boundary layer, dimensionless parameters in free and forced convective heat transfer, heat transfer correlations for flow over flat plates and through pipes, the effect of turbulence; heat exchanger performance, LMTD and NTU methods; radiative heat transfer, Stefan- Boltzmann law, Wien’s displacement law, black and grey surfaces, view factors, radiation network analysis

ISRO Scientist Electronics Engineering Syllabus

Electromagnetics

• Maxwell’s equations: differential and integral forms and their interpretation, boundary conditions, wave equation, Poynting vector.
• Plane waves and properties: reflection and refraction, polarization, phase and group velocity, propagation through various media, skin depth.
• Transmission lines: equations, characteristic impedance, impedance matching, impedance transformation, S-parameters, Smith chart. Rectangular and circular waveguides, light propagation in optical fibers, dipole and monopole antennas, and linear antenna arrays.

Networks, Signals, and Systems

• Circuit analysis: Node and mesh analysis, superposition, Thevenin’s theorem, Norton’s theorem, reciprocity. Sinusoidal steady state analysis: phasors, complex power, maximum power transfer. Time and frequency domain analysis of linear circuits: RL, RC, and RLC circuits, solution of network equations using Laplace transform. Linear 2-port network parameters, wye-delta transformation.
• Continuous-time signals: Fourier series and Fourier transform, sampling theorem and applications.
• Discrete-time signals: DTFT, DFT, z-transform, discrete-time processing of continuous-time signals. LTI systems: definition and properties, causality, stability, impulse response, convolution, poles and zeroes, frequency response, group delay, phase delay.

Electronic Devices

• Energy bands in intrinsic and extrinsic semiconductors, equilibrium carrier concentration, direct and indirect band-gap semiconductors.
• Carrier transport: diffusion current, drift current, mobility and resistivity, generation and recombination of carriers, Poisson and continuity equations.
• P-N junction, Zener diode, BJT, MOS capacitor, MOSFET, LED, photo diode and solar cell.

Digital Circuits

• Number representations: binary, integer and floating-point- numbers. Combinatorial circuits: Boolean algebra, minimization of functions using Boolean identities and Karnaugh map, logic gates and their static CMOS implementations, arithmetic circuits, code converters, multiplexers, decoders.
• Sequential circuits: latches and flip-flops, counters, shift-registers, finite state machines, propagation delay, setup and hold time, critical path delay.
• Data converters: sample and hold circuits, ADCs, and DACs.
• Semiconductor memories: ROM, SRAM, DRAM.
• Computer organization: Machine instructions and addressing modes, ALU, data-path, and control unit, instruction pipelining.

Control Systems

• Basic control system components: Feedback principle; Transfer function; Block diagram representation; Signal flow graph; Transient and steady-state analysis of LTI systems; Frequency response; Routh-Hurwitz and Nyquist stability criteria; Bode and root-locus plots; Lag, lead and lag- lead compensation; State variable model and solution of state equation of LTI systems.

Communications

• Random processes: autocorrelation and power spectral density, properties of white noise, filtering of random signals through LTI systems.
• Analog communications: amplitude modulation and demodulation, angle modulation and demodulation, spectra of AM and FM, super heterodyne receivers.
• Information theory: entropy, mutual information, and channel capacity theorem.
• Digital communications: PCM, DPCM, digital modulation schemes (ASK, PSK, FSK, QAM), bandwidth, inter-symbol interference, MAP, ML detection, matched filter receiver, SNR, and BER, Fundamentals of error correction, Hamming codes, and  CRC.

Analog Circuits

• Diode circuits: clipping, clamping, and rectifiers
• BJT and MOSFET amplifiers: biasing, ac coupling, small signal analysis, frequency response. Current mirrors and differential amplifiers.
• Op-amp circuits: Amplifiers, summers, differentiators, integrators, active filters, Schmitt trigger,s and oscillators.

ISRO Scientist Computer Science Engineering Syllabus

Programming and Data Structures

• Programming in C
• Recursion
• Arrays, stacks, queues, linked lists, trees, binary search trees, binary heaps, graphs.

Algorithms

• Searching, sorting, and hashing.
• Asymptotic worst-case time and space complexity.
• Algorithm design techniques: greedy, dynamic programming, and divide-and-conquer.
• Graph traversals, minimum spanning trees, shortest paths

Theory of Computation

• Regular expressions and finite automata.
• Context-free grammars and push-down automata.
• Regular and context-free languages, the pumping lemma.
• Turing machines and undecidability.

Compiler Design

• Intermediate code generation, Local optimization,
• Data flow analyses: constant propagation, liveness analysis, common subexpression elimination, Lexical analysis, parsing, syntax-directed translation, Runtime environments

Operating Systems

• concurrency and synchronization.
• Deadlock.
• CPU and I/O scheduling.
• Memory management and virtual memory.
• File systems, System calls, processes, threads, inter-process communication,

Databases

• ER-model.
• Relational model: relational algebra, tuple calculus, SQL. Integrity constraints, normal forms.
• File organization, indexing (e.g., B and B+ trees).
• Transactions and concurrency control.

Computer Networks

• Concept of layering: OSI and TCP/IP Protocol Stacks; Basics of packet, circuit and virtual circuit- switching;
• Data link layer: framing, error detection, Medium Access Control, Ethernet bridging;
• Routing protocols: shortest path, flooding, distance vector and link state routing; Fragmentation and IP addressing, IPv4, CIDR notation, Basics of IP support protocols (ARP, DHCP, ICMP), Network Address Translation (NAT),
• Transport layer: flow control and congestion control, UDP, TCP, sockets; Application layer protocols: DNS, SMTP, HTTP, FTP, Email

Digital Logic

• Boolean algebra.
• Combinational and sequential circuits.
• Minimization.
• Number representations and computer arithmetic (fixed and floating point).

Computer Organization and Architecture

• Machine instructions and addressing modes.
• ALU, data-path, and control unit.
• Instruction pipelining, pipeline hazards.
• Memory hierarchy: cache, main memory, and secondary storage; I/O interface (interrupt and DMA mode).

ISRO Scientist General Aptitude & Reasoning Syllabus

• Numerical reasoning,
• Logical reasoning,
• Diagrammatic reasoning,
• Abstract reasoning, and
• Deductive reasoning

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