This paper describes an analysis of pronunciation problems in Japanese utterances by Korean speakers, and evaluation methods of a CALL (Computer Assisted Language Learning) system for teaching Japanese pronunciation to Korean speakers. To develop a CALL system, the pronunciation problems of Koreans must be understood. Firstly, Japanese utterances by adult Korean speakers were evaluated by Japanese native speakers. Then, the Japanese pronunciation problems of Korean speakers were analyzed. Finally, evaluation methods were developed. Speech recognition technology was used to compare Japanese utterances by a learner with that by a native speaker. With the proposed methods, intelligibility scores which indicate the similarity between the learner's speech and the Japanese native's speech are automatically calculated.