In order to increase the density of W-Ni-Mn alloy, some alloying elements were added into W-Ni-Mn alloy for improving sintering characteristics. SEM and EDS were used to study the microstructure of sintered W-Ni-Mn alloy. The results show that MnO can be deoxidized by aluminum and silicon, to purify the binder phase;Zn and Sn can reduce the sintering temperature. The two approaches improve the density of W-Ni-Mn alloy.