AbstractTwo hundred and thirty‐eight cervical lesions ranging from normal to malignant were examined for overexpression of p53 protein. Whereas p53 protein was identified in 62 per cent of invasive squamous cell carcinomas, 11 per cent of invasive adenocarcinomas, and 7 per cent of squamous cell carcinomasin situ, no staining was found in adenocarcinomain situ, dysplastic tissue, condyloma, and normal tissue. In 9 per cent of the positive cases of invasive squamous cell carcinomas. 5‐50 per cent of the tumour ceiis were immunoreactive for p53 protein, whereas the other positive specimens were characterized by only rare p53‐positive cells. We conclude that in invasive cervical carcinomas widespread overexpression of p53 protein is unusual, but occasional positive nuclei can be found frequently. Furthermore, our results indicate that altered expression of p53 protein may be involved in the progression of cervical carci