A crankshaft is the most critical component, and it can dominate the life of the engine. Nowadays an orbital grinding is widely used to grind a crankshaft. In this study, static analysis is done to find deformation of an orbital grinding system due to weight, modal analysis is done to obtain the natural frequencies, and harmonic analysis is done to investigate the compliance. It is found that all the results show that first frequencies are found to be near 70-80Hz. The machine will be weak to vibration near 70-80Hz. It is also found that the peak value of x compliance is smaller than that for other axes, and grinding in the x direction will be more stable than grinding in other direction.