Background: pterygium is a tumoral lesion of benign behavior and multifactorial ethiology, where conjunctive proliferates with fibro vascular growing and it invades cornea in warmer climates. It can be primary or recidivant and according to the level that reaches the corneal invasion four grades are described. It is a mass of subepitelial tissue with elastotic degeneration, on a bottom of hyaline degeneration, new blood vessels and inflammatory changes, the epithelium that covers it can show acanthosis, dyskeratosis and dysplasia. Taking into account these characteristics, it is classified as angiomatous, fibrous and mixed. Objective: to identify clinical and histopathologic characteristics in operated patients of primary pterygium. Methods: a descriptive, transverse study was carried out in the Educational Surgical Hospital Dr. Octavio de la Concepción y de la Pedraja in Camagüey from September to December 2016. The universe was constituted by 77 operated patients. Variables of biological and clinical characterization were related. Descriptive statistics for distribution of frequencies correlating the variables with absolute values and percents was used. Ethical aspects were respected for investigation in humans. Results: the biggest number of sick persons was among 40 to 59 years of age, and those studied were white. According to the grade of corneal invasion the biggest frequencies were for grade III, followed by grade II and grade IV. In the examined samples epithelial hyperplasia was informed, hyaline and elastotic degeneration, slight dysplasia, vascular structures associated or not to other fibrous changes, chaliciforms cells in the epithelium, chronic inflammation and deposit of pigments. Pterygium of fibrous type prevailed over the fibrous one and on the angiomatous. Conclusions: keeping in mind that the pterigion is an illness that impacts with great frequency in the Cuban population, the study of its clinical and histopathologic characteristics is vital for good ophthalmologic practices The result of the histopathologic study was similar to those described by other authors. Its histopathology continues showing as a benign tissue of the conjunctiva. DeCS: PTERYGIUM; CORNEAL DISEASES; PATHOLOGY; ADULT; EPIDEMIOLOGY, DESCRIPTIVE.