Criminal Procedure is a process of producing,collecting,transferring and applying evidence.The legis-lator has restricted the evidence information as the basis of judgment for some legitimate reasons.The crimi-nal evidence rules are essentially a kind of evidence information restraint mechanism,which promotes the u-nification of the accurate fact-finding and the guarantee of other values.The regulation function of criminal evidence rules can be realized in three ways:firstly,the rule of trial evidence,which regulates the presenta-tion and application of evidence during the trial stage;secondly,the rule of pre-trial evidence,to regulate the production,collection,custody and application of evidence information before trial;thirdly,it is to take both pre-trial and trial as a whole,comprehensive regulation of the flow of evidence information is achieved through rights protection.These three modes of regulation are rooted in different litigation ideas and have dif-ferent operational modes.China's criminal evidence system lacks unified legislative approach,and needs fur-ther improvement.