Avidin-biotin-peroxidase labeling technic was used to localize the binding sites of Concanavalin agglutinin (Con A), Ricinus communis (RCA-I), Ulex europaeus (UEA-I), and Limus flafus (LFA) in the cervical epithelia afflicted with condyloma (2 cases), moderate dysplasia (6), severe dysplasia (3), carcinoma in situ (9), squamous cell carcinoma (18), adenosquamous carcinoma (2), adenocarcinoma (1), and glassy cell carcinoma (1). Normal squamous epithelium displayed binding sites predominantly located on the cellular membranes for all the tested lectins except UEA. Normal glandular epithelium showed cytoplasmic localization of the lectins. Neoplastic transformation of squamous epithelium was associated with an increased intensity of the reaction and the appearance of the binding sites in the cytoplasm. UEA binding has changed from negative in normal epithelium to moderately positive in dysplasia and strongly positive in carcinoma. Invasive squamous carcinomas demonstrated an extremely variable pattern of lectin binding, some with very high intensity, allowing easy recognition of malignant cells even in minute metastatic foci.