Abstract: Covering width is an important index of the panoramic aerial camera, so the effect of imaging starting angle error on the sawtooth result of panoramic aerial camera imaging was analyzed in detail. Based on introducing the operating mode and scheduling of panoramic aerial camera, the relationship between the ratio, which was defined as , of image margin difference to covering width, target slope angle, transverse scanning angle and imaging starting angle error was given. When panoramic aerial camera was on operating, one special constant angle was reserved for the imaging starting angle. The imaging starting angle error would be appreciably high when this method was used. So improved iterative arithmetic was imported. In the improved method, the imaging starting angle error of every frame was recorded and was used to correct that of next frame. At last, experimental result was given. Result shows that the root-mean-square of imaging starting angle errors are respectively 0.045 and 0.005 when general and improved methods are used. And the corresponding ranges of are0.009 1,0.014 8 and 0.001 0,0.001 7. Compared with general method, the imaging starting angle error is reduced to be 1/9 when induced iterative arithmetic is used, and the corresponding maximum of is 0.001 7, which could comply with engineering requirement.