Using the sensitive peroxidase, anti-peroxidase immunohistological technique, carcinoembryonic antigen (CEA) was studied in formalin-fixed, paraffin-embedded cervical specimens from 225 patients. CEA was demonstrated in 33% of moderate dysplasia, 78.5% of severe dysplasia, 79% of in-situ carcinoma and 78% of invasive carcinoma. CEA was not demonstrated in normal squamous epithelium, squamous metaplasia, reserve cell hyperplasia nor in mild dysplasia.