Abstract: The influence of temperature change on the stress and deformation of support system of foundation pits attracts more and more people's attention. Based on the Winkler foundation model and the elastic resistance method, the equivalent spring stiffness is proposed to improve the method for calculating the temperature stress in the horizontal strut of a foundation pit. A formula for calculating the change of axial force and horizontal displacement of strut due to temperature change is derived. Compared with the pre-method, the proposed method is simpler. Besides, it can also be used to estimate the change of axial force and horizontal displacement of strut due to temperature rise.