The purpose of this study is to examine two English pronunciation teaching methods for Korean students. The Korean students were trained by an English professor and a Korean professor. They learned how to pronounce English diphthongs using some English words. The English professor asked them to repeat after him and corrected their pronunciation. The Korean professor provided phonetic explanation of the English diphthongs such as the way to use lips and the tongue, etc. and applied phonological information of Korean vowels while correcting their pronunciation. We recorded their pronunciation both before and after they were trained. The results show that the Korean professor`s training methods are more effective than those used by the English professor. (Dongguk University).