This study investigated the effectiveness of TikTok short videos in improving students’ vocabulary mastery at SDN 46 Bengkalis. The research was motivated by students’ difficulties in understanding, remembering, and using English vocabulary due to the use of conventional teaching methods that were considered less engaging. The research employed a quantitative approach using a pre-experimental design with one-group pre-test and post-test. The sample consisted of 24 fifth-grade students of SDN 46 Bengkalis. The data were collected through vocabulary tests consisting of 20 multiple-choice questions administered as pre-test and post-test. The data were analyzed using validity and reliability tests, descriptive statistics, normality test, and paired sample t-test with the assistance of SPSS version 27. The findings showed that the students’ mean score increased from 61.04 in the pre-test to 81.67 in the post-test. In addition, the paired sample t-test indicated a significant difference between pre-test and post-test scores (p < 0.05), suggesting that use of TikTok short videos was associated with an improvement in students’ vocabulary mastery. Therefore, TikTok short videos can be considered an engaging and potentially effective learning medium for elementary school students.