An experimental study of dissimilar friction welding was conducted using 15mm diameter solid bar in chrome molybdenum steel (SCM440) to carbon steel (S45C) not only to optimize the friction welding conditions, but also to investigate the fatigue performance. The main friction welding parameters were selected to endure good quality welds on the basis of visual examination, tensile tests, Vickers hardness surveys of the bond of area and HAZ, and microstructure investigations. In this study, the specimens were tested as welded. For fatigue strength, the notched specimens for the optimal conditions were rotary bending fatigue tested. The results were compared with S-N curves for the base metals.