Abstract: Four models of PC frame structures with different prestressing ratio designed according to the current aseismic codes in our country were established in OpenSees software based on fiber section element. Firstly, the numerical pseudo-static analysis of a single span PC frame was performed, and the comparison between the experimental and numerical results demonstrated the accuracy of the numerical model. Then, static elasto-plastic analysis were conducted on each PC frame model on OpenSees platform. For the prestressed concrete beams designed by secondary-crack control level, the amount of non-prestressed reinforcement was investigated theoretically. The analytical results show that PC frames are difficult to achieve ‘strong column and weak beam’ failure mode under strong earthquakes and plastic hinges appear prematurely at the bottom of column. A reasonable increase in the prestressing ratio could improve the yield mechanism, increase the structural ductility and enhance the structural seismic capacity. Therefore, the paper suggests that the prestressing ratio should be increased to 0.8 for PC frames.