Abstract: A Cu-based shape memory alloy(SMA) composite reinforced with macroscopic graphite particulates (Gr/Cu-based SMA) was prepared by using air pressure infiltration process, and its damping behavior and damping mechanism were studied by using a multifunction internal friction apparatus. The results show that the damping capacity of the composite was higher than that of the matrix alloy, and the internal friction of the composite increased with the increase of graphite particulate volume fraction and strain amplitude, and with the decrease of the diameter of graphite particulates. The intrinsic damping of the substrate and the graphite particulates, dislocation damping and interface damping were the main damping mechanisms of the composite.