Abstract: It is main reason that spacecraft system failures and anomalies attributed to the space radiation environment.Many case histories of spacecraft failures and anomalies documented from 1972 through 1997 attributed to the natural space radiation environment.And it provides an overview of seven major areas of spacecraft system failures and anomalies,effects on various spacecraft subsystems,related analysis methods and countermeasures.There are several related projects to on-orbit spacecraft management.The primary focus is to present more than better understanding of the space environment and its effects will enable spacecraft designers and managers to more effectively minimize program risks and costs,optimize design quality,and achieve mission objectives.