This study explores the effectiveness of educational TikTok videos in enhancing junior high school students' English vocabulary at SMP Negeri 18 Semarang. Using a quasi-experimental design with a pre-test and post-test control group, 65 students were involved: 33 in the experimental group using TikTok and 32 in the control group using conventional methods. Vocabulary improvement was measured through form, use, and meaning. The Mann-Whitney U test revealed a significant difference (p = 0.002), supporting the alternative hypothesis that TikTok positively affects vocabulary acquisition. The effect size (r = 0.4) indicated a moderate but meaningful impact. Students using TikTok showed greater engagement, enthusiasm, and retention. However, factors like instructional design and motivation also played important roles. The findings suggest that TikTok, when used strategically, can be an effective supplementary tool for vocabulary learning. Future studies should investigate long-term retention and assess the impact of various types of TikTok content on learning outcomes.