The purpose of this study was to investigate the effect of sinc phosphate cement on the enamel surface of extracted teeth. The tooth was placed in a test tube, which was subjected to 5ml of 0.2M acetate buffer at pH 4 by window technique. The calcium content of the acetate buffer was determined by the Perkin-Elmer Model 303 Atomic Absorption Spectrophotometer. The obtained results were summarized in the following. 1. The solubility of enamel is 0.92mg/cm². ml in control group. 2. The solubility of enamel is increased by treating these with zinc phosphate cements. 3. The solubility of enamel is 0.69mg/cm². ml by treating with Lee Smith cement. 4. The solubility of enamel is 0.30mg/cm². ml by treating with G-C´s cement.