Based on the establishment of equivalent single degree of system in the push-over method, the equal ductility demanding spectrum of a steel-concrete composite fame structure was obtained, and the composite fame was analyzed by using inelastic static push-over method of ANSYS software. The several degrees of freedom system were converted to single degree of system based on displacement mode, the equivalent acceleration-equivalent displacement curve was built, and the spectrum acceleration-spectrum displacement curve of the composite fame structure was established according to the current seismic code. So the seismic performance of the structure was evaluated. The reliability of the push-over method was validated by comparing with the inelastic dynamic time-history analysis.