AIM: To investigate the effect of hypoxia on the proliferation of mouse corneal epithelial cells in vitro. METHODS:Mouse corneal epithelial cells(MCEs) were cultured in normoxia (210mL/L O2 and 50mL/L CO2) and hypoxia (20mL/L O2 and 50mL/L CO2), respectively. Colony forming efficiency (CFE) and cell proliferation were determined. The expression of corneal epithelial progenitor cell marker p63 and K19 was investigated by immunostaining. RESULTS: Normoxic colonies were smaller compared with colonies formed in hypoxia. CFE was (12.50±1.50)% in hypoxic cultures, which was similar compared with normoxia cultures [(11.13±1.86)%, P >0.05)]. Cell proliferation was enhanced in hypoxia. Progenitor markers p63 and K19 were expressed in most cells under both normoxic and hypoxic conditions. CONCLUSION: Murine limbal epithelial progenitor cells can be efficiently expanded in hypoxic conditions.