Purpose: The authors investigated the effects of acoustic cues (i.e., pitch height, pitch contour, and pitch onset and offset) and phonetic context cues (i.e., syllable onsets and rimes) on lexical tone perception in Cantonese-speaking children. Method: Eight minimum pairs of tonal contrasts were presented in either an identical phonetic context or in different phonetic contexts (different syllable onsets and rimes). Children were instructed to engage in tone identification and tone discrimination. Results: Cantonese children attended to pitch onset in perceiving similarly contoured tones and attended to pitch contour in perceiving different-contoured tones. There was a decreasing level of tone discrimination accuracy, with tone perception being easiest for same rime-different syllable onset, more difficult for different rime-same syllable onset, and most difficult for different rime-different syllable onset phonetic contexts. This pattern was observed in tonal contrasts in which the member tones had the same contour but not in ones in which the member tones had different contours. Conclusion: These findings suggest that in addition to pitch contour, the pitch onset is another important acoustic cue for tone perception. The relative importance of acoustic cues for tone perception is phonetically context dependent. These findings are discussed with reference to a newly modified TRACE model for tone languages (TTRACE).