Vocabulary is a vital element in language learning.At the fourth grade of SD Negeri 1 Sukoharjo has serious problem in mastering vocabulary. It shows that the students do not pay attention to the teacher explanation. Thus, on the average 55 % of the students get score under the criteria of success (65 from 0 â€“ 100 scale). To solve this problem, the researcher offers sevo game. The research approaches are quantitative and qualitative. The design of this research is classroom action research. The subjects are 18 students. The research procedures are preliminary study and research action implemented in the form of cycles. Research instruments consist of observation guide in learning process, test, questionnaire, and field notes. The results of them are the data sources of the research. The result of the study shows 8 students (44%) passed the test on the preliminary study, 11 students (61%) passed the test on the first cycle, and on the last cycle 17 students (94%) passed the test. Based on the comparison, it is concluded that sevo game can be used to improve the studentsâ€™ vocabulary mastery. Based on the result found, the writer suggests to the teacher and the students to use sevo game in teaching learning vocabulary.