We conducted a hospital-based case-control study in Algiers, Algeria. A total of 198 cervical carcinoma (CC) cases (including 15 adeno- and adenosquamous carcinomas) and 202 age-matched control women were included. Human papillomavirus (HPV) DNA in cervical cells was evaluated using a PCR assay. Odds ratios and corresponding confidence intervals were computed by means of unconditional multiple logistic regression models. HPV infection was detected in 97.7% of CC cases and 12.4% of control women (OR = 635). Nineteen different HPV types were found. HPV 16 was the most common type in both CC cases and control women, followed by HPV 18 and 45. Twelve types (HPV 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 66 and 73) were found as single infections in CC cases. Multiple HPV infections did not show a higher odds ratio for CC than single infections. In addition to HPV infection, husband's extramarital sexual relationships with other women (OR = 4.8) or prostitutes (OR = 3.2), residing in a rural environment for most of one's life (OR = 4.9) and indicators of poor sanitation or poor hygiene were the strongest risk factors for CC. Oral contraceptive use was unrelated to CC risk, while multiparity emerged as a significant risk factor after adjustment for sexual habits. Intrauterine device users showed a lower CC risk than nonusers. The role of major risk factors, except inside toilet, was confirmed in the analysis restricted to HPV-positive women. The distribution of HPV types in CC cases and control women in Algeria is more similar to the one found in Europe than the one in sub-Saharan Africa, where HPV 16 is less prevalent. A vaccine against HPV 16 and 18 may be effective in more than 3/4 of CCs in Algeria.