Abstract name : shaumi fitria student number : 1506102020065 study program : english education title : the influence of using i spy game towards students’ vocabulary mastery key words: i spy game, vocabulary mastery vocabulary is one of the basic and most important aspects in learning a language. in the learning process, learners need to know lots of words of the target language with such various techniques. students’ vocabulary mastery is influenced by many factors. in this research, researcher wants to know if there is significant influence towards the students’ vocabulary mastery by using a game called i spy as the technique used in this research. this research is a quantitative approach with pre-experimental design, one group pretest-posttest. the subjects of this research were the first grade students of junior high school. the class chosen as the experimental class was vii2 which consisted of 30 students at smp negeri 2 takengon with 15 female students and