For the scroll wrap in small-parameter scroll compressor, its temperatures under stable operating condition are analyzed and the simulations for thermal deformation of scroll wrap height are performed. By fitting the simulations, a formula for simplified calculation of thermal deformation of scroll wrap height is proposed. The maximum deviations between simplified calculations for thermal deformation of orbiting scroll wrap height in a scroll compressor and simulations by FEM are no more than 5%, so the simplified calculation for thermal deformation of scroll wrap height is feasible. The experiment for the scroll compressor in which the orbiting scroll wrap is modified based on simplified calculation shows the modification for scroll wrap considering deformation of scroll wrap height can improve obviously the performances of scroll compressor. At the same time, reducing the temperature differences between the discharge and suction temperatures, limiting scroll wrap height, using the material having lower thermal expansion coefficient, and selecting a larger thickness of scroll wrap are other several effective means to reduce the influence of thermal deformation of scroll wrap height and to improve the performance of scroll compressor in engineering practice.