In the application of the defendant’s character evidence in criminal proceedings, in practice, there are dilemmas such as the lack of legal evidence qualifications and the review process. In this regard, the traditional judicial concept that all character evidence is not used should be revised based on the theoretical definition of character evidence. The preliminary admissibility of the criminal defendant’s character evidence is clarified by focusing on the proving role of the criminal defendant’s character evidence for specific criminal acts, and taking its indirect probative value as the radius. With the review rules of extraterritorial character evidence as a frame of reference, the review process from "single evidence review" to "multiple evidence verification" is constructed. The review of single evidence should focus on whether the character evidence has the least relevance to the facts to be proven. In multiple evidence corroboration reviews, it should be ensured that character evidence can be reasonably corroborated with other evidence.