This paper analyzes Electromagnetic Pulse(EMP) effects on the whole system, expatiates on the testing techniques of each coupling point and the experimentation validation techniques of the whole system. High altitude Electromagnetic Pulse(HEMP) produced by nuclear explosion is a big threat to electronic systems on the ground. Some of them are exposed to the field directly, some are in a shield, and others are exposed partly. Therefore, HEMP field should be analyzed firstly before analyzing the HEMP effects on an electronics system. The HEMP effects and the generation processes of the voltage and current induced inside and outside the system are analyzed in detail; different simulation tests and the special objects corresponding to them are introduced.