The influence of consonant aspiration on the F0 contours of tones in Mandarin Chinese was tested in continuous speech by reference to a minimal pair of syllables, /ta/ and /tha/, which differ only in terms of aspiration. It was found that, consonant aspiration affects the fundamental frequency (F0) of the following vowel. The onset F0 of a tone is higher following unaspirated consonants than following aspirated consonants, and the magnitude of the differences are related to the tone itself as well as the preceding tone. The underlying mechanisms of this effect, as well as its interaction with other effects on F0 contours, are discussed.