The photoluminescence (PL) intensity of porous silicon in H2O2 under illtimina-tion increases first, and then decreases with increasing processing time, and the PL intensity reaches its maximum when the processing time is one minute. Under illumination in air, the PL degradation of porous silicon without processing is substa-ntia1, but that for the processed porous silicon gets much smaller. The Fourier-transform infrared (FTIR) absorption shows that the localized vibration related to oxygen increases greatly but all kinds of Si-H bonds decrease obviously. Contrasting the variation of the FTIR with that of the PL in the processes, we conclude that the luminescence does not come from the Si-H bonds on the surfaces of porous silicon.