SUS316 steel is a high-quality material with high durability and good corrosion resistance. Because of these properties, it is widely used in medicine, chemicals, or equipment manufacturing in the food industry. In the numerical simulation of the forming process for SUS316 sheet material, the stress–strain curve serves as a critical input parameter that significantly influences the accuracy of the simulation results. In this study, tensile test samples of SUS316 material according to Japanese standard [JIS-G4303] with a thickness of 1 mm and its dimensions according to ASTM E8 standard were cut in rolling direction (RD) of 0°, 45°, 90°. Subsequently, the influence of the RD on plastic deformation was examined and discussed. Finally, the flow stress curves of SUS316 steel, derived from the Voce, Swift, and Kim-Tuan plasticity models, were constructed and compared with experimental results to assess their predictive accuracy. In subsequent studies, the most suitable flow stress model is applied to simulate the forming process.