The shock test and analysis of the equipment in the Mars probe for the large shock response generated by separation of the probe and the Long March 5 launch vehicle is discussed. The reliability of the equipment is analysized after shock test. The Strength-Stress model is proposed to judge if the reliability is affected. The half-sine wave impulse shock condition of components offered by the manufacturers is known as Strength, and the half-sine wave converted by the shock response spectrum of the equipment is known as Stress. The two values are compared. This method can be regarded as an assisting methodto judge the reliability of the equipment after shock test, and also can be regarded as the criteria of shock resistance of the equipment.