A Stray radiation analysis program suitable for use on PC computer is described. The program is ideally suited for quick estimates of stray light performance in well-baffled optical systems, to calculate the single scatter of main mirror, double scatter of baffle-mirror, and diffraction-scatter of baffle edge in a similar form of some large program of stray radiation analysis. The prediction made by the program for a typical system is comparable with the result of the APART large analysis program.