The research entitled about The Effectiveness of the Hiragana Random Letters Game Media to Improve Japanese Vocabulary Comprehension. This study using a true experimental design of quantitative method, with the sample is MAN II Yogyakarta class XI IBB period 2018/2019. The study aims to determine the significant effectiveness of the hiragana random letters game media to knowing Japanese vocabulary comprehension and the sample response about game method. The result of the effectiveness media in class XI IBB MAN II Yogyakarta is showed by normalized formula again is experimental class N gain1= 0.86 > control class N gain2 = 0.12. It can be concluded that the Ha hypothesis which is hiragana random letter game media has significant effectiveness in developing Japenese vocabulary comprehension is accepted. Meanwhile the H0 hypothesis which there is no significant effectiveness of the hiragana random letters game media in developing Japanese vocabulary comprehension is rejected. Not only that, the hiragana random letter game was responded positively by the students and the response can be seen in the quisionnaire. Many students thought that learning japanese vocabulary by using hiragana random letters helps them understand the vocabulary easily.