Multilayer SiNx/Si/SiNx thin films are deposited on silicon substrate by bipolar pulse reactive magnetron sputtering technology combined with rapid thermal process technology. Raman spectra and photoluminescence (PL) spectra are used to investigate the microstructure and luminous property of the films influenced by different annealing temperatures. The results of Raman spectra show that crystal and amorphous silicon quantum dots have formed in multilayer SiNx/Si/SiNx films by the high temperature annealing, with the Xc of 30% and the average size of about 6.6 nm. But the results of PL indicate that the average size of the crystal and amorphous silicon quantum dots are about 3.79 and 3.03 nm, respectively. In addition, luminous mechanism of PL consists of the defect states of SiNx and the quantum effects of quantum dots and the defect states of SiNx is the main luminous mechanism.