Phonetic typological studies suggest that syllable duration is inversely correlated with the accompanying tone's approximate average f₀, and tones with dynamic f₀ movement tend to be in longer syllables rather than shorter ones. Systematic instrumental investigations on tone-duration interaction remain scant, however; existing studies might be confounded as tonal context may impact duration realization due to phonetic constraints on tonal movement. This study investigates the effect of tonal environment on the durational realization of tones in Cantonese, showing that tone-dependent duration variation is governed by the tonal context. Implications of these findings for existing phonetic typology concerning tone-duration interaction are discussed.