This study investigates the impact of the Busuu platform on students' vocabulary acquisition and explores students' perceptions of using the platform to learn new vocabulary. The research was conducted with 15 students from SMK Negeri 1 Jeumpa Class X TKJ, employing a mixed-methods approach combining
quantitative and qualitative data collection. Quantitative data were collected through pre-test and post-test assessments to measure vocabulary acquisition, while the qualitative data were collected through opend-ended questionnaire to understand students' perceptions and experiences. The findings showed that the use of the Busuu platform significantly improved students' vocabulary acquisition. The results of the pre-test showed that only 20% of students were classified as successful, while 80% were unsuccessful. After the intervention, the result of the post-test showed a significant improvement, with 87% of students classified as successful and only 13% as unsuccessful. Statistical analysis using a paired sample t-test confirmed this improvement with a mean difference of -29.00 (p = 0.000), demonstrating a significant impact of the Busuu platform on vocabulary acquisition. Qualitative findings highlight positive student perceptions of the Busuu platform. Three key themes emerged: (1) an enjoyable learning experience, where students appreciated interactive features such as word-picture matching and pronunciation practice; (2) increased motivation, driven by immediate feedback and engaging tasks; and (3) a positive shift in attitudes toward vocabulary learning, with students expressing greater confidence and enthusiasm compared to traditional methods.This study confirms the efficacy of the Busuu platform in improving vocabulary acquisition and fostering positive attitudes toward language learning. The integration of interactive features and personalized feedback makes Busuu platform a valuable tool for modern language learning. This research contributes to the growing body of technology-based language learning research, and provides practical insights for educators seeking innovative approaches to vocabulary teaching.