Abstract: In the event of fire, high-rise building structures may be subjected to horizontal loads, which are crucial in the fire-resistant design of high-rise building structures. In order to investigate the fire performance of SRC-RC frame structures under horizontal loads, finite element analysis method is used in this paper to systematically analyze the deformation behavior, failure mode, working mechanism and fire resistance limit of these structures subjected to horizontal loads. In the analysis, many parameters such as the fire location, axial compression ratio of columns and horizontal load ratio are taken into account. The analysis results show that horizontal loads have a significant impact on the fire resistance of SRC frame structures. There are two typical failure modes observed under the combined action of horizontal loads and fire. The first is the overturning failure of the frame, during which the fire resistance limit of the frame decreases with the increase of the shear force on the fire-exposed floors, and the second is the frame beam failure, in which the change in the fire resistance limit of the frame is relatively small. Finally, the failure modes of frame structures under horizontal loads and a simplified calculation model for fire-resistant design are proposed.