Guide ways of ultra-precision machine tools always have sufficient stiffness and guiding precision. But guide way rails deformation caused by oil film pressure and slider offset lead to oil film clearance change which affects static stiffness and guiding precision. An inside-slider hydrostatic guide way is designed, and its static characteristics are analyzed. As a result, the effect of slider offset on stiffness and guiding precisions is obtained. A FE model of guide way is established. An elastomer of virtual material properties is used to simulate oil film, so that the relationship between oil film clearance and pressure can be represented in a certain range. Static stiffness and guiding precision are obtained considering deformation of rails.