Objective. A hospital-based case-control study was conducted to identify characteristics of women at high risk of developing cervical cancer with special reference to sexual behavior in Korea. Methods. Histologically confirmed cases of invasive cervical cancer were selected from the Department of Gynecology, Seoul National University Hospital between September 1992 to May 1995 (n=203). Women with normal pap smear tests and women free of past history of any malignancies were regarded as controls (n=827). Information on risk factors were collected by both a self-administered questionnaire and a direct interview. Results. Uterine cervical cancer risk was higher in women with a less educated spouse (Ptrend=0.0003), women with a family history of cervical cancer (adjusted odds ratio [OR]=2.20., 95% confidence interval [CI] 1.21-4.01), women of shorter height (Ptrend=0.02), women with early age at first full term pregnancy (Ptrend=0.0005), and women who have had multiple full term pregnancies (Ptrend=0.006) by the multiple linear logistic analysis. Particularly noteworthy was a significant decreasing trend in the adjusted OR with the age at first sexual intercourse increasing (Ptrend=0.002) after adjusting the number of sexual partners. The husband's indecent sexual history showed a borderline significance (Ptrend=0.07). Conclusions. This study confirmed that the risk factors of cervical cancer in Korea are similar with those found in other countries. J Epidemiol, 1997; 7 :117-123.