Image space scanning optical system with tilt mirror usually only scanning imaging in one dimension, when tilt mirror is scanning imaging in two dimension, the effect of the tilt mirror’s coupling motion of azimuth and pitch can not be ignored. The basic forms of scanning optical system with tilt mirror were analyzed, and the influence of two-dimensional motion of the image space scanning optical system with tilt mirrors was analyzed. The incident optical axis direction and the spot size on the optical window at the different two-dimensional scanning angles were calculated. A method of image space two-dimensional scanning optical system with tilt mirror design and analysis were proposed. Building the image space two-dimensional scanning optical system model with Zemax, and the imaging performance, optical axis direction and window blocking at different angle of scanning were simulated and analyzed. Under different azimuth and pitch angles, the MTF of the optical system was greater than 0.4 at 17 lp/mm, and the max window blocking of the window was less than 21.4%.