W-10Ti alloys were prepared with high purity 6 μm and 300 nm tungsten powder and TiH2 powder as raw materials, which were mixed according to different graded proportions, compacted by the cold isostatic press, and sintered by the liquid sintering method. The density of W-10Ti alloys prepared with tungsten powder of different sizes was measured, and the microstructures and phase constituent of alloys were analyzed by XRD, SEM and TEM. The results show that the density of W-10Ti alloy prepared with all 6 μm tungsten powder and TiH2 powder is only 85%, but W and Ti are distributed uniformly, and almost single phase solid solution is formed in the microstructure. The density of W-10Ti alloy prepared with all 300 nm tungsten powder and TiH2 powder is up to 97%, but more Ti rich solid solution is formed. When W-10Ti alloys prepared with W powder of different sizes and TiH2 powder, the single phase W-rich solid solution in microstructures is increased and the density of alloys are lowered with the decrease of the graded ratio of nanoscale to micronscale tungsten powder. When the graded ratio of nanoscale W to micronscale W is 1:2, the density of W-10Ti alloy is 95%, and more single phase W-rich solid solution is formed.