Through the analysis of the distribution function of the rosette scan infrared subpixel seeker, a fast target detection technology of equalization of resolution of image space was proposed.In consideration of the nonlinear characteristics of the image space,by making full use of the information of each pixel, this technology realizes the subpixel target recognition, and improves the target detection probability. The experimental results show that this method is feasible and can be realized in real time in DSP system.