In order to research the plasticity of the Cu-based bulk amorphous and the influence of rare earth element on the mechanical properties of the amorphous, the Cu50-xZr42Al8Gdx (x=0, 2, 4) alloy rods with 3.0 mm in diameter were prepared by the suspend melting-copper mold suction casting. The structure and glass forming ability of the alloys were analyzed by X-ray diffraction (XRD) and differential scanning calorimetry (DSC), respectively. Subsequently, through the compression performance testing and the fracture morphology observation, the effect of rare earth element Gd on the mechanical performance and the fracture behavior of the samples were investigated. The results show that the structure of the rods is composed of amorphous phase. The samples possess larger thermal stability and good glass formation ability. With the increase of Gd content, the brittleness of the samples is enhanced gradually. Fracture mode presents brittle fracture.