Friction welding is one method of connecting workpiece materials using heat arising from friction between the workpiece surface. This heat arises because of the friction between the two workpiece materials that are still and moving, then pressed using the pressure force that has been set. This research was conducted to determine the effect of friction pressure variations on friction welding for 304 stainless steel pipe materials and brass pipes on tensile strength, hardness and microstructure of the pipe joints. The material used is 304 stainless steel pipe with a length of 75-80mm with a diameter of 21.5mm and a thickness of 2mm, and a brass pipe with a diameter of 22mm with a thickness of 1.5mm. Friction welding is carried out by utilizing the lathe rotation, at a speed of 1000 rpm and using frictional pressures of 30, 40, and 50 MPa. This research was conducted to determine the structure, hardness value, and tensile strength of 304 stainless steel pipe joints and brass pipes. The results of this study are the increasing friction pressure given the grain size of the microstructure of the joint area resulting from friction welding is getting smaller. The highest hardness value of the connection area for brass pipe is found in a variation of 30 MPa friction pressure that is equal to 114.2 VHN, and for stainless steel pipes there is a pressure variation of 40 MPa with a hardness of 237.7 VHN. the lowest hardness on brass pipe joints is found in variations of friction pressure 40 and 50 MPa which is 103.0 VHN and for stainless steel pipe at 30 MPa pressure variation that is 220.6 VHN. The highest yield of tensile strength at 40 MPa friction pressure is 304.67 MPa but still lower than the yield of tensile strength in raw stainless steel material that is 605 MPa, and brass raw material is 497.32 MPa. The variation of friction pressure recommended in this study is 40 MPa friction pressure in terms of the tensile strength test results obtained.