A flux-splitting procedure of compressible flow analysis based on steam properties is presented. To compute the high-speed steam flow, a new generalized Roe average is introduced. Density and internal energy per unit volume are selected as thermodynamic independent variables. Pressure and temperature in a superheat region or wetness mass fraction in a wet region are calculated by using steam table. To improve computational efficiency, discretized steam table matrix is made. This table has 201×201 nodes for density and specific internal energy. For the accuracy and continuity of steam properties, the second order Taylor expansion and linear interpolation are used. The computational results of one-dimensional shock tube problem are compared with the theoretical results. These show that this numerical technique is valid both from high pressure region to low pressure region and from superheat region to wet steam region.