Research in the field of second language acquisition indicates that exposure to subtitled movies as comprehensible input generally enhances the acquisition of vocabulary. This paper reports on an experimental study which seeks to explore the effects of using subtitled movies on the vocabulary acquisition of English for Specific Purposes (ESP) university students in Algeria. The aim is to possibly find empirical evidence using ESP programs in Algeria as a case study. In order to achieve this aim, a sample of participants were recruited for the research and were randomly divided into control group, those who were asked to watch a movie without subtitles, and treatment group, those who were exposed to the movie with subtitles. The two groups were later asked to complete a Vocabulary Test (VT), which involved thirty vocabulary items identified from the movie. The VT was quantitatively analyzed using the one-way ANOVA procedure to determine the statistical significance of vocabulary acquisition. The findings indicate that using subtitled movies clearly enhances the learning of new vocabulary, and that the vocabulary acquisition of the treatment group is much greater than the acquisition of the control group. As a conclusion, it is noted that these results are generally congruent with current theory in the field. It is recommended that ESP teachers in Algeria need to encourage the use of multimedia in their language classrooms towards enhancing their learners’ vocabulary acquisition.