A local composition expression has been derived from the Guggenheim＇s quasi-chemical equation. On this basic a thermodynamic model, the quasi-chemical local composition model (QCLC) was established. To examine its capability for correlation and prediction, Baxter＇s adhesive hard sphere mixtures were used, and an improved numerical method was proposed to estimate their thermodynamic properties. By means of this method the excess properties of the mixtures composed of four kinds of adhesive hard spheres were calculated. The activity coefficients from QCLC model were compared with those from the Wilson, NRTL and UNIQUAC equations. Results show that among these models, the QCLC model is the best one for correlation and prediction.