After the treatment of porous Si by "amine immersion and rapid thermal oxidation", the peak position of the photoluminescence spectra has a blue shift to 500nm. Only a little change in photoluminescence was observed after 160d storing in dry air. FTIR spectra indicate that the compositions of such treated sample are mainly silicon and oxygen. ESR signal shows that the blue/green light-emitting sample has rather low density of dangling bonds. These results demonstrete that the quantum confinement effect and surface states play a key role in blue/green light emitting. This method is simple and practicable, to make blue/green light-emitting samples and its success ratio can achieve 70%.