Being one the modern high quality industrial welding process especially for stainless steels and titanium alloys. TIG welding process has been has been researched for decades in order to define its parameters such as welding speed, current and arc length to improve the weld penetration. Hence it is a popular technique for joining thin materials-the thickness of the work piece is in general restricted to less than 6 mm-in manufacturing industries. In this study, AISI 321 and 316L stainless steel sheets of 4 mm of thickness were used as welding metals. Thus, AISI 321 welding metal couples, AISI 316L welding metal couples and AISI 321 and 316L welding metal couples were selected to ensure a combination of similar and dissimilar metals. The filler metal rod was made of 316L SS. The specimens were cut in dimensions of 150 x 30 x 4 mm as using an abrasive cutter, then the V weld butt joint configuration with single groove of 37.5 o ± 2.5 o groove angle by a lathe machine. The welding current was 200 A and TIG welding process was performed manually in single under argon shielding gas atmosphere. After TIG welding process, the separate metallographic preparations, then microscopic and macroscopic examinations of the specimens, also hardness measurements of specimens were made. The rest of them was shaped for tensile strength measurement using Instron Universal Testing Machine. The hardness of the specimens were observed being altered in the range of 145-151 HRV(average) and their tensile strength values in the scale of 345-400 MPa (average).