Saravan potent earthquake with Ms=7.7 on April 16th, 2013, severly struck widespread regions in Iran, Pakistan, Afghanistan, some parts of India and Persian Gulf littorial states. In this research co-seismic stress changes owing to the temblor calculated by means of coulomb stress model. Based on the results most aftershock activities occurred in areas with increasing static stress. This confirms that Saravan fault system impressed by the temblor.