The aim of the research was to find out the effectiveness of subtitled videos for teaching vocabulary. This research used quasi experimental method in which the sample was based on the school policy. Two classes were chosen seventh E as control group and seventh G as experimental group. Pre-test and post-test were used to find the data. The test was in multiple choice forms consisting 20 items for each test. T-test formula was used to find the data. The result of the research showed that there using conventional teaching. It could be seen on the result of computation of t-test, where t-result is 6.30 and t-table 1.671 at the significant level α=0.05 in df=58. The result was higher than t-table (6.30>1.671). It means that the hypothesis that authentic material was effective for teaching vocabulary was accepted.