Background: A graded series of ocular surface changes has been described throughout the bulbar conjunctiva. The most advanced changes occurring directly over the pterygium surface, confirming that pterygium is indeed an ocular surface disorder. Purpose: Pterygium is characterized as invasive, proliferative fibro-vascular altered conjunctival tissue. The extensive vascular network is likely to significantly contribute to the progression of the disease. The present study aims to correlate the findings obtained from studying the epithelium of true primary pterygium by impression cytology technique and microscopic picture. Design: Prospective clinical study. Methods: This study is a prospective study designed to analyze data of 20 eyes of 20 patients presenting to the Department of Ophthalmology at "Ain Shams University" and at the "Research institute of ophthalmology" with clinically diagnosed pterygium. Results: Histopathological study identified pathological change in epithelium and subepithelial fibrovascular tissue of the pterygium. Conclusion: Histopathological examination of the epithelium of pterygia revealed epithelial changes most prominent directly above the head of pterygium.