Vocabulary is an essential component of language that everyone must recognize and use to communicate effectively with others. People with a limited vocabulary find it difficult to communicate and express themselves effectively, both orally and in writing. And the purpose of vocabulary mastery is for students to develop a great knowledge of language skills, especially in learning English. Western movies, particularly Hollywood movies, can assist people learn English, and have a significant impact on enhancing people's English abilities. Meanwhile, in this research, the researcher tries to figure it out whether watching western movies can affect the vocabulary mastery of non-English department students of UNISMA. Researcher used descriptive qualitative design and chose University of Islam Malang to conduct the research, especially Non-English department students. For the instrument of this research, researcher use a survey, which distributing a questionnaire and an interview, and for subjects of this research, researcher chose twenty students to fill the questionnaire, and interviewing six respondents who scored better on the questionnaire. However, this research was conducted online because there are some obstacles. The finding of the research shows that watching western movies can help respondents improve their vocabulary mastery and add a lot of new words. Aside from that, adopting western movies as a learning medium may help learners boost their self-esteem, improve their pronunciation, and acquire the new accents employed by the characters in the movie, as well as other abilities like listening and speaking. Therefore, the conclusion is that using western movies for learning English can help the students improve their vocabulary mastery, and because learners take note of the new vocabulary they have discovered, it can help them with simply discovering and remembering the meaning of new vocabulary. Not only that, teaching English can be more effective and enjoyable if teachers use western movies as a learning media. Key Words: English Learning, Vocabulary, Western Movies, Non-English Department Students