Mg2Ni1-xCux alloys (x=0, 0.2, 0.4) were synthesized by two steps: induction melting and then ball milling. The composition and microstructure of the alloys were analyzed by XRD and SEM/EDX, respectively. Mg2Ni phase was observed in all of the 3 alloys. The increase of Cu amount led to the formation of Mg2Cu phase and Cu11Mg10Ni9 phase. The hydrogen absorption/desorption properties were tested on PCT measurement apparatus, and the results show that the hydrogen absorption/desorption properties of the alloys can be improved by the addition of Cu.