In order to research the comprehensive influence of gas-thermal-solid and the cooling fin on the deformation and stress of scrolls, the 3D models of orbiting and fixed scrolls are created. On the basis of finite element method(FEM) and indirect coupling method, the deformation and stress of orbiting scroll, fixed scroll and assembly of scrolls are investigated under the conditions of forced by gas force and thermal-solid coupling. The calculation results show that the maximum deformation occurs in the top of scroll teeth head and the maximum stress occurs in the bottom of the scroll teeth head when the orbiting scroll and fixed scroll are analyzed separately. The deformation and stress of the fixed scroll are slightly larger than the orbiting scroll. Temperature load has a greater effect on the deformation and stress of orbiting and fixed scroll. The deformation of scrolls decreases due to the mutual interference and restriction after the assembly. The suitable assembly clearance is got by the analysis of the maximum deformation and stress variation trend of the scrolls under the conditions of different axial and radial clearance. The comparative analysis of the cooling fin affect on deformation of the scroll teeth is carried out. The investigation results show that cooling fin can reduce the deformation of the scroll tooth and increase the reliability of operation.