The purpose of this paper IS to investigate the aspects of errors of English stress by Korean students. In this experimental study, 17 students participated and read 120 words which are divided into three types-the beginning, the middle, and the advanced-according to the level of words. As a result of acoustical judgement, there were a greater number of errors In the advanced level of words, and the more syllables the words have, the more errors occurred, tins means Korean students who learn English as a second language have trouble realizing the right stress in words with larger numbers of syllables and the more advanced level. Furthermore it is interesting that Korean students imposed the primary stress on the second syllable when producing words with stress in the first, third and forth syllables.