Spot welding is a welding process that is widely used in the automotive industry due to for joint similar or dissimilar materials such as manufacturing vehicle bodies. Spot welding is widely used because it’s simple process of the process compared to other welding methods. Setting a fixed time variation and welding voltage will result in a welding joint quality. The purpose of this study is to determine the effect of welding time variations on dissimilar spot welding connections to determine physical and mechanical properties. This study uses a different type of material between stainless steel 430 with a thickness of 1mm and low carbon steel SPHC JIS G 3131 with a thickness of 1 mm, length 80 mm x width 25 mm (standard AWS D8.9-97). The time variations used are 3, 4, 5, and 6 seconds. The fixed stress used in sopot welding is 2.02 V. The test carried out is testing the microstructure, hardness, and shear tensile strength. The results of the microstructure observation show that the variation of welding time affects the change in the size of the diameter of the nugget, the microstructure grains in the HAZ region, and the weld metal. The highest average hardness value was found in the area of stainless steel 430 metal ± 419.25 HV at 5 seconds variation and low carbon steel metal weld ± 367.13 HV at 6 seconds variation. Tensile test results provide the highest average tensile load capacity at 5 seconds time variation of 5395,173 N, while the highest average shear strength value is at 4 seconds time variation of 217.51 N / mm². From the research data it can be concluded that the influence of time variations is very influential on the diameter of the nugget, physical and mechanical properties of the structure also affect the testing of microstructure, hardness and the value of the tensile load capacity.