Soonhyun Hong. 2017. Effects of Perceptual Training on the Identification of American English Monophthongal Vowels by Korean Listeners. Studies in Modern Grammar 95, 55-80. In this study, we tried to demonstrate that a forced choice vowel identification training with feedback for three weeks with naturally produced /hVd/ signals of multiple English talkers’, effectively facilitated 47 Korean listeners to learn to identify English monophthongs. The subjects were assessed before, after and two months after the training with an identification test composed of a group of vowel signals produced by multiple novel talkers. The results showed that the subjects’ identification accuracies improved sharply after training and the improvement persisted for two months. Furthermore, the response latencies at the identification test got drastically shortened at Posttest and the shortened latencies also persisted for two months. The results suggest the possibility that through three-week training, most of the training effects could be transferred from the short-term memory to the long-term memory.