The effects of powder loading and sintering temperature on the mechanical properties of a metal injection molded (MIM) tungsten heavy alloy are studied. The properties of MIM products are compared with those of traditional pressed/sintered products with the same compositions. The following optimal properties have been attained for the 97W 2Ni 1Fe alloy made by the MIM process with a powder loading of 47vol% and sintered at 1 530 for 2 hrs: b=936 MPa,02=649 MPa,=114%,HRC=31 They are much better than those of pressed/sintered alloy.