The AZ91D magnesium alloy engine brackets in JH70 motorcycle was produced successfully with the pressing machine on the basis of billets prepared by decreasing pouring temperature combining with die casting.The results indicate that the microstructure of the brackets with compact structure is composed of primary α-Mg phase and eutectic phase which consists of net-like secondary α-Mg phase and γ-Mg17Al12 phase.The hardness and tensile strength of T4 treated components are decreased by 4.5% and by 3.1%,respectively,while those of T6 treated ones are increased by 30.1% and by 14.0%,respectively,and elongation of the components treated by T4 and by T6 is increased by 17.6% and by 40.5%,respectively,compared with that of ones without treatment.