Abstract
The paper provides a new reliability analysis method of complicated system witch is called "The sub'system Method". On the base of reliability analysis of each sub 'system .First we establish their extreme condition function and then we applies the the reliability analysis method with mutual force to establish and calculate the reliability u.f system. the system life predication and reliability distribution of system. The experiments and calculations shows that this method is simple and easy and efficient.At last. examples are given to illustrate the implementation of the sub 'system method ofreliability analysis in au/omobile power Transmission test.