This study investigates whether native Hmong speakers' first language (L1) lexical tone experience facilitates or interferes with their perception of Mandarin tones and whether training is effective for perceptual learning of second (L2) tones. In Experiment 1, 3 groups of beginning level learners of Mandarin with different L1 prosodic background (Hmong, Japanese, and English) took a perception test on Mandarin tones. Both the English and Japanese groups outperformed the Hmong group in perceptual accuracy of Mandarin tones. In Experiment 2, 18 learners with different L1 background received either perception training only or perception with production training on Mandarin tones for 6 hours within 3--4 weeks. Both training paradigms were effective for perceptual learning of Mandarin tone contrasts as the two training groups' perceptual accuracy improved significantly at post-test compared with a control group. Although Hmong speakers initially had more difficulties in perception of Mandarin tones than the other 2 groups, they are by no means disadvantaged by their L1 prosodic background as they gain L2 experience after intensive training. (Contains 6 figures and 2 tables.)