This study investigates the enhanced effect of timber infill walls on the seismic behavior of traditional Chinese timber frames. Two 1/2 scaled traditional Chinese timber infill walls (TIWs), two 1/2 scaled timber frames with timber infill walls (TFTIWs) and one 1/2 scaled timber frame (TF) were fabricated and tested under low-cyclic reversed loading. The failure modes, strength, stiffness, and energy consumption capacity of the TIWs and the TFTIWs were obtained, and the effects of the TIWs on the seismic performance of the TFTIWs were investigated. The results showed that the TIWs can increase the stiffness and ultimate bearing capacity of the TF, up to 60% and 80%, respectively. The strength degradation coefficient of the TFTIWs was slightly higher than that of the TF when the inter-story drift ratio exceeded 0.02 rad, and the TIWs helped to mitigate the strength degradation of the TFTIWs. It was also found that the TFTIWs had a higher cumulative energy dissipation when compared with the TF (up to a 60% increase), indicating the TIWs had reasonably good energy dissipation capacity. When the TIWs generated a solid contribution to the carrying capacity and energy dissipation of the TF, the lateral drift thresholds were 1/100 and 1/43 of the column height, respectively. Furthermore, the TIWs and TFTIWs presented a good ductility, and the TIW could effectively reduce the pull-out amount of the tenon from the mortise of the TF; however, the TIWs had little influence on the stiffness degradation level or improvement of the ductility of the TF.