Abstract: Regarding the issue that thermal errors caused by non-uniform temperature field distribution severely restrict the further improvement of rotary table performance, and existing studies, due to the lack of in-depth analysis of static thermal error mechanisms and internal temperature fields, result in difficulties in distinguishing between heat source-dominant effects and motion coupling effects in dynamic analysis as well as insufficient thermal error compensation, a research method combining theoretical analysis and multi-measurement-point temperature field monitoring is proposed. This method systematically reveals, for the first time, the temperature stratification of "oil return surface > spindle > guide rail" inside the rotary table under static working conditions, as well as the circumferential temperature characteristics of "high temperature near the oil return port and low temperature far from the oil return port". A high-precision fitting of the temperature evolution process is realized based on a periodic correction model, with the fitting determination coefficient > 0.9995. Meanwhile, the floating amount test verifies the robustness of oil film stiffness against thermal deformation under static conditions, with the floating amount maintained within ±1μm. The research results fill the gap in the systematic study of static thermal errors and provide experimental data and theoretical support for the dynamic thermal behavior analysis of precision rotary worktables.