Acoustic realization of word accent differs among languages. While, in Japanese, it is fully represented by an F 0 contour of a word, English word accent is characterized by power, duration, F 0 , vowel quality and so forth. In addition to the difference in syllable structure between the two languages, that in word accent makes it even more difficult for Japanese students to master correct pronunciation of English words. It indicates that the development of an automatic evaluation method of English word accent, as one of English teaching tools, will be helpful especially to Japanese students. In this paper, as the first step to the development, a detection method of accent in English words spoken by Japanese is proposed, where syllable-size HMMs are built using positional information of the syllables and adequately detected syllable boundaries are used for the detection. Results of accent detection experiments show 90 % and 93 % as detection rates of Japanese students and native speakers respectively.