In this research, the effect of active listening training given to fourth grade students on their vocabulary was examined. Pre-test--post-test control group trial model, which is one of the semi-experimental trial models, was used. Besides, "Vocabulary Test" developed by the researcher was applied to experimental and control groups before the experimental implementations. The students in the experimental group were given a weekly two-hour-course of active listening training for eight weeks. The students in the control group were provided the materials forming the content of active listening training but they were made to study these materials with a weekly two-hour-course by traditional listening practice for eight weeks. At the end of the experiment, the test introduced as pre-test was also used as post-test in order to assess the differences between the groups. As the findings obtained from the research were analyzed, it was seen that active listening training positively contributed to vocabulary development levels of fourth grade students. Together with this, the other conclusion obtained from the research was that the students' listening comprehension achievement contributed to learning new words.