Abstract: Microsegregation and homogenization of superalloy GH105 ingots were studied by optical microscope, scanning electron microscopy and EDAX. The results show that the severe segregated elements are Ti and Mo, and the segregation degree can be reduced by a two-stage heat-treatment of homogenization. The homogenization process can be effectively predicted by the homogenizing equation, which agrees with experimental results as a whole, while there are some errors between experimental results and those predicted by the residual segregation parameter model.