Objective To evaluate the expression of the type Ⅰ growth factor receptor family [epider mal growth factor receptor (EGFR), ErbB2 and ErbB3] by the epithelial cells in pterygium. Methods Immunoflurescent staining and Western blotting were performed to detect the expr ession pattern and quantity of EGFR, ErbB2 and ErbB3 proteins in the epithelia o f 15 patients with primary pterygium and 12 subjects with normal conjunctiva.Results In immunofluorescent staining, the EGFR protein was present in the basal cells w hile the ErbB2 and ErbB3 were expressed by the superficial cells in normal conju nctival epithelium. Of the pterygium cases 15, 11 were stained by EGFR, ErbB2 a nd ErbB3 in the full thickness of the epithelium and showed stronger staining co mpared with the control group. Four of them showed a similar staining pattern t o the normal conjunctiva group. The density of protein bands detected by Wester n blotting for all three growth factor receptors was consistent with the immunof luorescent staining. Compared with normal conjunctiva, stronger protein bands o f these three receptors were found in all of the pterygium specimens, in which E GFR, ErbB2 and ErbB3 were expressed in the full thickness, as shown by immunoflu orescent staining. Conclusions The increased expression of EGFR, ErbB2 and ErbB3 proteins was present in ptery gium, which indicated that pterygium is a disorder with abnormal proliferation. The abnormal expression of EGFR, ErbB2 and ErbB3 by the epithelium and the comm unication with cytokines in the stroma in pterygium may be a key pathogenic fac tor in this disorder. Objective To evaluate the expression of the type I growth factor receptor family [epider mal growth factor receptor (EGFR), ErbB2 and ErbB3] by the epithelial cells in pterygium. Methods Immunoflurescent staining and Western blotting were performed to detect the expr ession pattern and quantity of EGFR, ErbB2 and ErbB3 proteins in the epithelia of 15 patients with primary pterygium and 12 subjects with normal conjunctiva. Results In immunofluorescent staining, the EGFR protein was present in the basal cells w hile the ErbB2 and ErbB3 were expressed by the superficial cells in Of the pterygium cases 15, 11 were stained by EGFR, ErbB2 a nd ErbB3 in the full thickness of the epithelium and showed stronger staining co mpared with the control group. Four of them showed a similar staining pattern to the normal The density of protein bands detected by Wester n blotting for all three growth factor receptors was consistent with the immun Compared with normal conjunctiva, stronger protein bands of these three receptors were found in all of the pterygium specimens, in which E GFR, ErbB2 and ErbB3 were expressed in the full thickness, as shown by immunofluorescent staining. Conclusions The increased expression of EGFR, ErbB2 and ErbB3 proteins was present in pteryiumium, which indicated that pterygium is a disorder with abnormal proliferation. The abnormal expression of EGFR, ErbB2 and ErbB3 by the epithelium and the comm unication with cytokines in the stroma in pterygium may be a key pathogenic fac tor in this disorder.