In this study, we investigated attitudes toward sexuality, the prevalence of sexual behaviors and contraceptive use among Chinese medical and nursing undergraduates, and relationships between attitudes toward sexuality and sexual and contraceptive practices among these participants. This was a descriptive, cross-sectional study carried out by using a Personal Attitude toward Sexuality Scale and Sexual and Contraceptive Questionnaire. The participants were recruited in the researcher's lectures. A total of 158 participants joined this study. Overall, Chinese medical and nursing undergraduates in this study held relatively conservative attitudes toward sexuality. The prevalence of sexually-active students was relatively low, and the percentage of contraceptive use among those sexually-active students was also low. Participants' attitudes toward sexuality had statistically-significant effects on their sexual and contraceptive practices. Nearly half of the sexually-active participants reported never using any contraceptive method during sexual intercourse. This finding has important public health implications, as young people represent the group with the largest rate of new infections of HIV/AIDS in China. A more comprehensive sexual education program that extends to college undergraduates and promotes the social acceptability of using contraception, specifically condoms, is needed.