Abstract: The cold-formed double C steel frame filled with steel plate walls is a new type of frame structural system. Three-story frame specimens of this new type frame were made and tested under low cycle reversed loading. The failure form, failure mode and seismic behavior of the frame were analyzed. The test results show that the frames with infill steel plate walls possess good capacity of energy-dissipation when they buckled, and the infill steel plate walls can improve the bearing capacity and stiffness of the cold-formed double C steel frame and ensure that the inter-story drift satisfies the requirement codified in the seismic design code. Based on the test results, a finite element model was established, and the parametric study on seismic behaviors of cold-formed double C steel frames filled with steel plate walls was performed considering the variation in height-thickness ratio of steel plate walls, height-width ratio and stiffness coefficient of frame column. At last, design suggestions were proposed based on the finite element parametric analysis.