Abstract: Objective To explore the role of Rab23 in melanogenesis induced by UVB in human melanocytes. Methods The human melanocyte PIG1 cells were irradiated respectively with UVB at 25 mJ/cm², 50 mJ/cm²and 100mJ/cm², and the western blot was performed to determine the expression of Rab23 and MITF in PIG1 cells.The protein of PIG1 cells treated with UVB at 50 mJ/cm²was extracted respectively after 0.5 h，1 h，2 h，6 h and 12 h，then the western blot was conducted to measure the expression of Rab23, MITF and gp100.PIG1 cells transfected by siRNA targeting Rab23 were treated with UVB at 50 mJ/cm², and its protein was extracted after 6 h, then the western blot was conducted to measure the expression of Rab23, MITF and gp100. Results UVB irradiation promoted the expression level of Rab23, MITF and gp100 in PIG1 cells in a positive dose-dependent and time-dependent manner, while the Rab23 inhibition in PIG1 cells decreased the expression level of MITF and gp100 induced by UVB of 50 mJ/cm²for 6 hours irradiation. Conclusion Rab23 is involved in the melanogenesis induced by irradiation with UVB, and the downregulation of Rab23 will decrease MITF and gp100 induced by UVB-stimulated.