The precoat film forming method of a film forming device having a loading table for loading the object, includes a deposition step of feeding processing gas inside the film forming device and depositing a precoat TiN film on the surface of the loading table and a stabilization step of reducing and stabilizing the precoat film on the loading table, wherein the precoat film formed on the loading table at the deposition step has a film thickness within a range such that even if the film thickness of the precoat film changes, a radiation heat quantity from the loading table becomes generally constant. Therefore, as the thermal stability is maintained at the film forming process of semiconductor wafers, it is possible to improve the reproducibility in the film forming process.