Abstract: To detect the influences of saliva contamination on the bond strengths of glass ionomer cement (Ketac, 3M), self-adhesive universal resin cement (RelyX, 3M) and self-etching adhesive systems (Contax, DMG). Methods：Artificial saliva was made. Human third molars were collected and 90 test specimens were made and divided into 6 groups according to three different cements and immerged into artificial saliva or not. The microtensile bond strength was measured. Results：In the control and contamination groups, microtensiles of RelyX and Contax cements groups were higher than that of Ketac groups. Microtensiles of 0 min and 3 min groups reduced more obviously than that of 6 min and 10 min which were not significantly different from control groups. Conclusions：Saliva contamination can influence the bond strengths of three cements in the early period of solidification. Bond strengths of glass ionomer cement reduce more than that of composite resin cement.