Microstructures and mechanical properties of porosity-graded Ti compacts were investigated in this study. To fabricate the porosity-graded compacts, Ti powders with three different particle sizes, 65, 189 and 374 μm were prepared by the plasma rotating electrode process (PREP) and the gas atomization process, and these powders were sintered with and without applied stress. Porosity and pore size of porosity-graded Ti compacts decrease significantly with decreasing initial powder size and by applying stress. The most porous layer (374 μm) is severely deformed in compression tests compared to other layers. The compressive strength of porosity graded-compacts is found to be in fairly good agreement with the strength of most porous layer. Bend strength of compact sintered at 1223 K and 1 MPa (223.3 MPa) shows a higher value than that of human bone (156.9 MPa).