In this paper,the statistical physics properties of sine-Gordon-Thirring model with impurity coupling are studied by means of functional integral method,and the effective potential is derived for weak coupling model by using a auxiliary Bose field technique.Free energy of the model is obtained from perturbation expansion of functional determinant.Moreover,the four-order statistical average values of two impurities and condensed term are calculated in weak coupling case.The diagrammatic presentations of the effective potential and statistical average values are also given.