The PCS system, which consist; of precast column and steel beam, has been developed and expected to achieve the effectiveness in the constructrability and improve the structural performance under earthquake. Low cyclic seismic test by ACI test program are carried out in order to verify the structural performance of the system. It is found that the system possesses the higher level of structural performance regarding to strength, stiffness, energy absorption and ductility than the requirements from criteria of the ACI.