As water affects the stability of asphalt mixture at high temperature， the changes of internal cohesion， internal friction angle and dynamic stability with water saturation rate were studied by vacuum water saturation test. The multi-function modified asphalt mixture， SBS modified asphalt mixture and matrix asphalt mixture were selected for comparative study. The results show that water has a great influence on the dynamic stability， internal cohesion and internal friction angle of SBS modified asphalt mixture and matrix asphalt mixture， and each parameter decreases with the increase of water saturation rate.The dynamic stability， internal cohesion and internal friction angle of the multifunctional modified asphalt mixture are almost not affected by the change of water saturation rate， showing a strong resistance to the water temperature coupling.