Abstract: In this article,Cu-Al-Mn-Ti shape memory alloys of different compositions which melted by non-consumable vacuum arc smelting furnace were investigated.The compositions,structures and phase transformation points were measured and analysed by means of scanning electron microscope and energy dispersive,metallographic microscope and micro-regidity machine.The results show that with certain mass fraction of Mn,the hardness of the alloys increased quickly when the mass fraction of Al increased and with certain mass fraction of Al,the hardness of the alloys increased slowly when the mass fraction of Mn increased.