This study explores the potential of Instagram as a supplementary vocabulary learning tool for English as a Foreign Language (EFL) students. With social media becoming increasingly integrated into daily life, the research examines how Instagram’s visual and interactive nature can support vocabulary acquisition. A quasi-experimental design was used, involving eleventh-grade students from SMKN 1 Banjarmasin. Participants were divided into two groups: an experimental group using Instagram and a control group using Facebook. Both groups received vocabulary instruction embedded in writing lessons over four sessions.

Pre-tests and post-tests were administered to measure vocabulary gains. Statistical analysis showed that students in the Instagram group achieved higher post-test scores than those in the Facebook group, indicating greater vocabulary improvement. These findings suggest that Instagram offers promising benefits as a tool for enhancing vocabulary learning in EFL contexts and supports the integration of social media into language education.