Aiming at the problem of pulses compression in a Tisapphire solid laser cavity, optical design software is employed to design the ultrashort pulses compressor with prism pairs, which can compensate group delay dispersion (GDD) can compress the ultrashort pulses. First, a model of pulses compressor with prism pairs is built by optical design software. And the linear relation between GDD and the distance of prism pairs are obtained by a macro which can compute GDD. Combined with GDD of a sapphire crystal, the compressor structure parameters match with GDD is obtained after optimization. When GDD of the pulses center wavelength are compensated, GDD of marginal wavelengths is reduced to 10 fs2 for a 100 fs pulse by using low-dispersion fused silica. Computation of GDD in an optical system using optical design software has the advantage of perceptual intuition, simpleness, low computational complexity.