We evaluated the epithelializing-promoting effect of a concentration of 0.005 mg/ml murine epidermal growth factor (mEGF), topically administered four times daily, on the herpes simplex virus 1 (HSV-1) corneal ulcers of the rabbit eye. The severity of the herpetic lesions was evaluated clinically, after the time course of the severity of epithelial keratitis, conjunctivitis, iritis, and stromal disease, for 14 days. A histological assessment was performed in the middle and at the end of the follow-up. The stromal keratitis of the mEGF-treated group was significantly more severe than the keratitis exhibited by the placebo-treated rabbits (Y=X3 X2*X4; p=0.0001). There were no significant differences in the degree of conjunctivitis, epithelial keratitis, iritis, and virus shedding between these groups. No evidence of a toxic effect of mEGF or placebo was found in the mock infected rabbit eyes. More studies, using different herpes virus strains and a broad range of murine and human EGF concentrations, are mandatory to ascertain the general significance of these results. Meanwhile, caution is recommended when using mEGF in the presence of an occult or manifest herpetic eye disease.