A series of 103 cervical biopsies derived from 103 women during July 1958 to September 1963 from Beijing, China were investigated with in situ hybridization for the presence of HPV6, 11, 16, 18, 31 and 33 DNA. The mean age of the patients was 46.1 + 10.6 years with a range of 24-74 years. Morphological features of HPV infection were found in 80 (77.7%) biopsies. Invasive cervical cancer was diagnosed in 43 biopsies and cervical intraepithelial neoplasia CIN I, CIN II and CIN III in 9, 9, and 27 cases, respectively. A total of 63.1% (65/103) of the lesions had morphological features of HPV infections associated with CIN or invasive carcinomas. Altogether, 31.1% (32/103) of the biopsies were shown to contain HPV DNA. Of the cases showing HPV morphology, 43.1% were HPV DNA positive. HPV16 (30/32) was the most frequent type, followed by HPV11 and 18, whereas no lesions with HPV6, 31 or 33 were found. A total of 19/43 (44.2%) of the invasive carcinomas contained HPV DNA. HPV DNA positivity and the grade of CIN showed a statistically significant correlation (P = 0.0011). Our study demonstrated the presence of HPV in cervical lesions among Chinese women in the late 1950's and early 1960's when a single sexual partner was the rule and also supports the concept that HPV has as an important etiological role in cervical cancer, the highest risk being associated with HPV type 16. The applicability of in situ hybridization in retrospective assessment is emphasized.