PURPOSE: This study was conducted to identify awareness levels in regard to preconception care and gender differences targeting single undergraduate students in their 20s. METHODS: The study participants were 867 single undergraduate students aged 20~29 (523 women, 344 men). This was a descriptive research, in which awareness levels of preconception care and pregnancy were identified the through questionnaire surveys. RESULTS: Gender differences in the awareness of reproductive care before conception were found. Generally, women's awareness of issues related to preconception care and pregnancy was higher than that of men. Women recognized risk factors in pregnancy (chi2=22.85, p<.001) and positive behaviors (chi2=10.91, p = .012) better than men. Women's awareness of preconception care was significantly higher than that of men (t=8.37, p<.001). The awareness levels of the students who completed a reproduction related class (t=3.16, p = .002) and the students who knew about folic acid (t=-10.78, p<.001) in preconception care were statistically significantly higher. CONCLUSION: The results indicate that the ways to educate and alert students to major risk factors before pregnancy and other reproductive care content before conception is to provide education both single women and single men.