Objective To investigate whether protamine hydrolytic peptide (PHP) from carp has a positive effect for treatment of oral ulcers. Methods The cell counting kit-8 assay was used to determine the effects of PHP at different concentrations (20, 40, 80, 160 μg/mL) on the proliferation of human oral epithelial cells (HOEC) and human oral keratinocytes (HOK). Lipopolysaccharide (LPS) was used to induce inflammation, and the anti-inflammatory effects were evaluated by cell proliferation rates and the mRNA expression levels of inflammatory factors interleukin (IL)-6, IL-1β, and tumor necrosis factor α (TNF-α). A cell scratch assay was performed to simulate the effect of PHP on oral ulcer healing. Results PHP promoted the proliferation of HOEC and HOK in a concentration-dependent manner within the range of 20-160 μg/mL. Compared with the control group, 160 μg/mL PHP increased the cell proliferation rates of HOEC and HOK by (32.05±3.82)% and (74.23±17.26)%, respectively (both P＜0.01). Moreover, compared with the LPS group, PHP reversed the LPS-induced inhibition of cell proliferation, with increases being (53.14±9.18)% and (76.45±8.16)% in HOEC and HOK, respectively (both P＜0.01). PHP at 40-160 μg/mL concentration-dependently reduced the mRNA expression levels of inflammatory factors in HOK; in the 160 μg/mL PHP group, the mRNA expression levels of pro-inflammatory factors IL-6, IL-1β, and TNF-α in HOK were only (46.48±4.42)%, (80.01±2.68)%, and (31.40±3.78)% of those in the LPS group, respectively (all P＜0.01). The cell scratch assay showed that 160 μg/mL PHP could effectively enhance the cell migration rates of HOEC and HOK, which were (1.84±0.17)-fold (P＜0.05) and (2.34±0.10)-fold (P＜0.01) that of the LPS group, respectively. Conclusion PHP can promote the proliferation and migration of oral cells, and exhibits significant anti-inflammatory activity, indicating its potential to accelerate oral ulcer healing.