Abstract: It is made an experiment on six T-shaped cross section column frame joints (2/3 reduced scale) under low-cycle repeated loads. According to different experiment aim, three groups are made. It is used that variable parameters of beam section height, the axis-pressed ratio and the hoop steel ratio to research their effects on cracks form and development, failure mechanism of the joints and the a seismic performance (including to anchorage of beam bars, joints ductility and energy consumption). It is pointed out that joints' crack shape appears reverse K but not the common rectangle joints' X shape, the forced mechanism is liable to the inclined press-pole mechanism. At the same time, it is also pointed out that the effect of the flange width of the joints on the aseismic performance of the joints relates to the bending stiffness ratio of beam and column.