The objectives of this research were (1) to study the results of using board game to improve English vocabulary for upper primary school students in small and medium-sized schools, and (2) to study the students' satisfaction after using board game. There were a total of 100 students: 50 students from small-sized schools, and 50 students from a medium-sized school. The samples were selected by using multi-stage sampling method. The research instruments were the English vocabulary board game, pre- and post-tests, a behavior observation form, an interview form, and a satisfaction evaluation form. Frequency, mean, percentage, standard deviation, and t-tests, were used to analyze the data. The research findings indicated that both small and medium-sized school students' scores were increased after using the board game at the statistically significant level of 0.001. Additionally, students' satisfaction was at a high level supported by the observation data and interview results.