The purpose of this research is to make a comparative study on the words of the Korean language and the Thai language. Linguistically, the Korean language and the Thai language have no ties of kinship, and in the relations between Korea and Thailand, there have been no exchanges historically enough to make mutual linguistic contacts between the two countries. Nevertheless, in Korean and Thai vocabularies, the words that have similar pronunciations and meanings can be found. Based on the fact that historically Korea and Thailand have all been influenced by Chinese culture, this research made a comparative study on Korean words and Thai words with the Chinese language being the medium. As the result of this research, it could be seen that considerable number of words that have similar pronunciations and meanings in basic words of the both countries existed. It was found that the words that have similar pronunciations and meanings appear diversely in basic words, and that homogeneous aspects were more noticeable than heterogeneous aspects. If, based on the results of this research, the similar words in the aspects of phoneme and meaning of words in the Korean language and the Thai language are collected widely and made into catalogues, they can be utilized for very useful learning materials not only for providing learning motivation but also for learning basic words by acting on positive metastasis for both Korean learners learning the Thai language and Thai learners learning the Korean language.