Personal cigarette smoking and exposure to passive smoke as risk factors for cervical cancer were examined in a population-based, case-control study conducted in Utah. Personal cigarette smoking was found to increase the risk of cervical cancer, after adjusting for age, educational level, church attendance, and sexual activity. The adjusted risk estimate associated with being a current smoker was 3.42 (95% confidence interval [CI], 2.10 to 5.57); for having smoked for 5 or more pack-years, it was 2.81 (95% CI, 1.73 to 4.55); and for having smoked at least 100 lifetime cigarettes, it was 2.21 (95% CI, 1.44 to 3.39). The adjusted risk estimate (also adjusted for actual cigarettes smoked) associated with passive smoke exposure for 3 or more hours per day was 2.96 (95% CI, 1.25 to 7.03). Risk from passive smoking was greater in women who were not smokers (odds ratio, 3.43; 95% CI, 1.23 to 9.54) than in women who smoked (odds ratio, 2.59; 95% CI, 0.23 to 29.24).