The purpose of this study was to analyze the frequency of vocabulary used in the middle school korean textbooks of the 2015 revised special education basic curriculum and to investigate the distribution of high frequency vocabulary, distribution of parts of speech, distribution of semantic domain. The results of this study are as follows: First, the number of individual vocabulary used in middle school korean textbooks is 2,824, and the total vocabulary is 22,059. The number of high frequency vocabulary is 210, which is used 12,786 times, and it occupies 57.96% of the total vocabulary. Second, the most common vocabulary of high frequency vocabulary is do (verb), followed by is (adjective), read (verb), and sentence (noun). Third, the parts of speech were followed by noun 1,685(59.65%), verb 591(20.92%), adverb 244(8.64%), adjective 210(7.43%), pronoun 29(1.03%), interjection 26(0.92%), numeral 22(0.78%), and determiner 17(0.60%). Fourth, the semantic domain was followed by actions 6,768(30.68%), other 2,690(12.19%), status 2,298(10.42%), education 2,190(9.93%), and people 1,779(8.06%).