Dissociative identity disorder (DID) is often presented in movies with the impression of danger, and its patients constantly acted as madness and crazy. With the rise of the internet, movies have become an essential communication channel, exerting a significant impact on people's understanding of the outside world. Thus, some scholars believe that movies may negatively influence people's impressions of DID since its figures have o ften been distorted. However, they failed to analyze in a more up-to-date and rigorous setting. Therefore, this study examined the connection between movies and DID, using questionnaires, movie analysis, and experiment in a more objective way. The paper concludes that DID is portrayed in distorted and biased ways in popular movies, and it influences the audiences to form and worsen the negative impressions toward DID and its patients, proving the expected hypothesis. Specifically, through movie analysis, the study found that movies still dramatize and associate the DID characters with violent behaviors, despite the movies give out some correct information in terms of the symptoms for DID. Moreover, by looking at the differences between pre-and post-screening surveys, people's impression of DID is generally negative. The willingness to get in touch with DID patients has gone down after watching DID-related movies. However, because the study only specifically examined nine participants in Dalton Academy, it is still a crucial task to extend such related research in a greater context, including a more diverse and generalizable population, further helping to understand and find ways to improve the social environment for DID patients and other mental disorders.