Abstract: The promotion of the reform in criminal action system with the trial as the center is vital in the current judicial reform of China. The right of viewing files given to the defendant is helpful to achieve equality of both parties of prosecution and defense. It can also help the judging party in the center to find out the facts of a case. From a perspective of following the rule of criminal litigation, giving the defendant such right is good to promote the valid defense and improve the litigation effi- ciency. Further, it can bring about some negative consequences, e. g. the defendant’s withdrawal of confession, retaliation of witnesses, and impair testifying. Therefore, the realization of the defendant’s right of reviewing files needs the guarantee and relief mechanism which is helpful to play its positive role as well as the prevention and penalty one to avoid its harmful results.