Loss of heterozygosity (LOH) at chromosome 3p frequently occurs in squamous cell carcinomas of the uterine cervix and indicates the probable sites of tumor suppressor genes that play a role in the development of this tumor. To study such recessive mutations involved in multistep cervical carcinoma, we separated tumors and normal DNA pairs from 43 invasive squamous cell carcinomas of the cervix on archived slides. We studied LOH using polymerase chain reaction (PCR) with 10 polymorphic DNA marker on the 3p12-26.1 region. HPV type 16 and 18 were preformed by PCR on tumor specimens. LOH at one or more loci was observed in 15 cases(35%). HPV DNA of any types was detected in 35 cases of all tumors (81%). HPV 16 was detected in 32 cases(74%) and HPV 18 in 9 cases (21%). In the 32 cases with positive HPV 16 infection, 9 (28%) had LOH, while in the 11 with negative HPV 16 infection, 6(55%) had LOH. Three cases in the 9 positive HPV 18 infection(33%) had LOH, while 12 in the 34 negative HPV 18 infection (35%) had LOH. Our results confirm that no relationship was found between 3p LOH and HPV.