In infrared remote target detection system,the aeral targets containing little piexls looks just like a spot.Objects on the ground have much influence on the detection of the targets.A infrared aeral target detection algorithm based on background suppression and feature points detection is presented.This method analyses the difference of gradient between ground and air and then partition them.Subsequently finding out the feature points which represent the location of the targets.This method is applicable for the spatial domain and low altitude target detection.Experiment results shows that the proposed algorithm is effective and convergent.