Objective: Cognitive behavioral therapy is one of the most mainstream psychological intervention methods at present. However, there are few studies on the differences in the effectiveness of cognitive behavioral therapy for different psychological disorders, as well as the differences between the effectiveness of online and offline cognitive behavioral therapy. Method: This paper makes a systematic quantitative analysis of 32 CBT experimental studies by using the meta-analysis method. Results: The results showed that the combined effect size of the random effects model was 0.373. Conclusions: The statistically significant level, indicating that cognitive behavioral therapy had a moderate positive effect on psychological disorders. There is no significant difference in the effect of cognitive behavioral therapy on different psychological disorders. Online CBT was less effective than offline CBT for anxiety disorders, and there was no significant difference in the effectiveness of online and offline CBT interventions for other psychological disorders. Therefore, CBT can be an effective option to intervene in psychological disorders such as anxiety and depression.