Objective To analyze the classification and clinicopathological features ofpremalignant and malignant epithelial neoplasia of the limbus. Methods Retrospective study. The clinical data of 69 patients with premalignant and malignant epithelial neoplasia of the limbus treated and diagnosed at the Tianjin Eye Hospital fiom 1990 to 2008 were reviewed. According to recent diagnostic criteria, the pathological data of all cases were examined again and the clinicopathological features were analyzed. Results In the 69 cases,45 cases (65.2%) were conjunctival intraepithelial neoplasia (CIN), 6 (8.7%) actinic keratosis, 18 (26.1%) squamous cell carcinoma. The mean age of the 69 patients was 53.6 years old, age ranged from 34～83 years, included 58 males (84%) and 11 females (16%). Forty-two cases (61%) arose from nasal limbus, 21 (30.4%) from temporal limbus, 6 (8.6%) extended into the surface of cornea. The actinic keratosis and CIN usually appeared as a fleshy or pink, flat or minimally elevated neoplasia. In the 45 CIN cases, 11 cases (24.4%) were mild CIN,34 (75.6%) severe CIN. In the 18 cases of squamous cell carcinoma, 12 cases were papillary squamous cell carcinoma, 6 were invasive squamous cell carcinoma, which generally larger and more elevated than CIN. The CIN, actinic keratosis and squamous cell carcinoma of limbus usually encroached the neighbor corneal epithelium, especially the squamous cell carcinoma easy invaded to superficial corneal stroma. Conclusions The CIN, actinic keratosis and squamous cell carcinoma of ocular surface mainly arise from the limbus of palpebral fissure, early accurate diagnosis and treatment is very important.