This research aims to improve students’ vocabulary mastery on the Job and Profession material in class VII H of MTsN 3 Kota Kediri through the implementation of the Vocabulary Self-collection Strategy (VSS) . This research is a Classroom Action Research (CAR) which is carried out in two cycles, consisting of an action plan, action implementation, observation or evaluation and reflection. The subjects of this research were 33 students of class VII H of MTsN 3 Kota Kediri, consisting of 15 boys and 18 girls. The results of data analysis of the average value of vocabulary mastery in the Job and Profession material cycle I is 80 and the average value of vocabulary mastery in the Job and Profession material in the second cycle is 88. From the data on learning outcomes it can be said that the learning outcomes of vocabulary mastery the Job and Profession material in cycle I to cycle II increased by 20%. It is recommended for English teachers to apply Vocabulary Self-collection Strategy (VSS) because it can improve vocabulary mastery results.

Aulia , Ilzam Karomatul .   (2024). Improving Students Vocabulary Mastery Using Vocabulary Self-Collection Strategy At MTsN 3 Kota Kediri. IAIN Kediri