In the study of the blue-violet emission properties of SiCN thin films, the emission intensity depends on the crystal structure of thin films. The annealing process is widely used in the preparation process of thin films as one of the effective means to remove defects and improve crystal quality. In this study, SiCN thin films were prepared by RF magnetron sputtering method utilizing sintered silicon nitride and graphite targets on Si/SiO2 substrates. Then, the samples were separately annealed from 600 to 1000℃ with an argon ambient for 30 min to optimize the photoluminescence performance of the blue-violet emission. The characterization results of XRD spectra show that the crystallinity of the SiCN sample with 900 °C annealing temperature is the best. The chemical bonds, and the surface morphology of the samples changed greatly after annealing. The RMS roughness of the SiCN samples increased from 1.9 nm to 20.19 nm before and after annealing at 900 °C. Also, the results of PL spectra show that the intensity of blue-violet emission at 365 nm reinforced 28.6 times after annealing at 1000 °C. It makes the SiCN film be a candidate of phosphor for blue-violet LEDs.