The purpose of this study was to examine documentary videos' effectiveness as writing teaching tools. The pre-test and post-test designs for the non-equivalent control group were used in this quasi-experimental investigation. The population of this study consisted of tenth-grade of a senior high school students. 36 students made up the sample. 17 students made up the control group, while 19 students were in the experimental group. Documentary videos were used to instruct the experimental group. A writing test served as the data collection tool. It was administered both before and after the test. The result shows that the t-test result was higher than the t- table or 2.70 > 1.69092. It can be concluded that documentary videos are effective for teaching writing.