The study aimed to investigate the effects of black soybean peptide (BSP) on the activity and collagen secretion of human skin fibroblasts induced by UVB. The cytotoxicity of different concentrations of black soybean peptide (0, 100, 200, 400, 800 μg/mL) on human skin fibroblasts was tested by MTT method. Human skin fibroblasts were divided into normal control group (NC), UVB group, and UVB+100, 200, 400, 800 μg/mL BSP groups. The cells in NC group and UVB group were cultured in normal medium. The cells in UVB+100, 200, 400, 800 μg/mL BSP groups were cultured for 24 h with 100, 200, 400, and 800 μg/mL black soybean peptide, respectively. MTT method and EdU staining method were used to test the cell viability. The contents of HA and HYP in the culture supernatant of cells were determined by ELISA method. The relative levels of COL1A1, COL3A1, MMP-1 and MMP-3 mRNA were detected by RT-qPCT. DCFH-DA probe was used to detect ROS. The levels of oxidative stress indexes (SOD, CAT, GSH-Px and MDA) were measured according to the kit instructions. The expression of Nrf2 (nucleus) and Keap1 protein was detected by western blotting. The black soybean peptide at the doses of 0, 100, 200, 400, 800 μg/mL does not affect the cell viability of human skin fibroblasts (F=0.597, P<0.668). Compared with UVB group, the relative cell viability and EdU positive rate, the content of HA and HYP, the relative levels of COL1A1 and COL3A1 mRNA, the levels of SOD, CAT and GSH-Px, and the relative levels of Nrf2 (nucleus) protein of UVB+100, 200, 400, 800 μg/mL BSP groups gradually increase, while the relative levels of MMP-1 and MMP-3 mRNA, the relative fluorescence intensity and MDA level of ROS decreased, and the relative level of Keap1 protein decreased (P<0.05). Black bean peptide can increase the vitality of human skin fibroblasts induced by UVB, promote collagen secretion, and inhibit oxidative stress by activating the Nrf2/Keap1 signaling pathway. Black bean peptide is expected to become additives in anti-aging cosmetics or whitening cosmetics.