Abstract: The microstructure and mechanical properties of P/M superalloy FGH4097 high-pressure turbine discs, which were made by argon atomization（AA）+hot isostatic pressing（HIP） process, were investigated. The results reveal that there are no obvious defects in the FGH4097 full-size disk prepared by AA+HIP+ heat treatment（φ0.2 mm-15 db）. No continuous network prior particle boundary（PPB） appears. There is tiny amount of thermally induced porosity（TIP） which is less than0.01%. The grain size is between ASTM 7-8 with no abnormal grains. The mean gamma prime precipitate size is 400 nm. The average tensile strength of the disc at room temperature, 650 ℃ and 750 ℃ is 1521 MPa, 1343 MPa and 1181 MPa respectively and the average yield strength is 1093 MPa, 1030 MPa and 985 MPa, respectively. The average room temperature impact energy is 46 J and the Brinell hardness is 394 HBW. The average stress rupture time of 650 ℃/980MPa is 714 h. The time of 0.2% creep is 277 h under 750 ℃/450 MPa. The average low-cycle fatigue life by stress control is 198,371 cycles at 650 ℃, 980 MPa. All mechanical properties meet the requirements of the FGH4097 high-pressure turbine disc technical standard, among them, creep and low cycle fatigue has high reliability of FGH4097-AA-HIP turbine disc. AA+HIP process could be applied to manufacture qualified FGH4097 high-pressure turbine discs.