Abstract: The pitch model of disyllable in Mandarin has been systemically studied on the basis of real materials ofdisyllable words through the techniques of polynomial curve fitting and VQ (vector quantization).The results show:(1) It is a practical and effective method in establishing the pitch model of disyllable through the techniques of polynomialcurve fitting and VQ.(2) Most pitch contours of the disyllable combinative tone have several sub-classes,though thediscretion of samples of some disyllables is small,therefore the average pitch model is not enough to express samples ofthem.(3) The difference between pitch contours is the highest Value of FO,which are correlated with the stresses of firstor second syllables.