To resolve the movingpoint target detection problem under the condition of low SNR, a new point targetdetection algorithm based on generalized edge extracted by order morphology filtering ispresented. Two steps of point target detection are adopted. First, background suppressionand generalized inner-edge of targets extraction are performed by order morphologyfiltering whose percentile is selected to pick out a small quantity of possible movingpoint targets. Then the motion constraint equation of the targets is set up according tothe image flow model. By use of the model, the true target motion trajectory is detectedin multi-frame successive image. The experiment results show that the method caneffectively and reliably detect the moving point target with SNR less than 3.