The existence of measurement noise in XRD analysis brings about unneglected effect on analysis of elementary composition. In this paper, in order to eliminate the effect of the noise of nano powder of YBaCuO in XRD, Short Time Power Spectral (STPS) was presented in this paper. And the anti-interference capability of STPS was systematically studied and improved in accordance with theoretical analysis. Experiments were carried out to test the anti-interference ability of STPS with inertia filtering. The simulation results show that STPS spectrum of signals with additive noise or multiplicative noise is quite clear. It indicates that STPS with inertia filtering can overcome influence from different noise, and it has better capability of anti-interference from additive noise comparatively.