In English as a Foreign Language (EFL) situations, it is important for educators to improve learners' sound recognition skill due to the variation of English found in the world. Furthermore, perceptual skill is a foundation leading to intelligibility in production. This study examined the effects of using High Variability Phonetic Training (HVPT) in computer assisted pronunciation training on the recognition and production of English phonemes, which are challenging for Japanese learners of English. Between pre-, mid-, and post-tests, the learners completed training sessions three times a week in two sound environments. The results demonstrated improvement in recognition skill with larger effects immediately after training. For production skill, however, the effects were not large, with a mixed outcome against the improvement in perception. Further research is suggested under a condition in which articulation practice immediately follows identification of individual training items. [For the complete volume of short papers, see ED590612.]