Abstract: Aiming at the problems of infrared moving object detection under the condition of rotating scan system, several methods were presented, and an optimal solution was selected. Firstly, according to the characteristics of infrared image, a projection matching method was used for the image registration. Aiming at the faults of traditional moving object detection methods, combining the advantage of frame difference and the classic self-adaptive background difference algorithm, a new approach was presented based on differentiated self-adaptive background difference algorithm, which made the pseudo moving object decreased obviously. At last, learning from the image registration, a method based on the least subtraction of mean gray value was proposed to remove the pseudo moving object effectively. Experimental results show that the presented algorithms can resolve the problems brought by the rotating scan mode quickly and effectively.