Many studies have examined differences in sexual behavior based on sexual orientation with results often indicating that those with same-sex partners engage in higher risk sexual behavior than people with opposite sex partners. However, few of these studies were large, national sample studies that also include those identifying as unsure. To address that gap, this study examined the relationship of sexual orientation and sexual health outcomes in a national sample of U.S. college students. The Fall 2009 American College Health Association-National College Health Assessment was used to examine sexual health related responses from heterosexual, gay, lesbian, bisexual, and unsure students (N = 25,553). Responses related to sexual behavior, safer sex behaviors, prevention and screening behaviors, and diagnosis of sexual health related conditions were examined. The findings indicated that sexual orientation was significantly associated with engaging in sexual behavior in the last 30 days. Sexual orientation was also significantly associated with the number of sexual partners in the previous 12 months, with unsure men having significantly more partners than gay, bisexual and heterosexual men and heterosexual men having significantly less partners than gay, bisexual and unsure men. Bisexual women had significantly more partners than females reporting other sexual orientations. Results examining the associations between sexual orientation and safer sex, prevention behaviors, and screening behaviors were mixed. Implications for practice, including specific programmatic ideas, were discussed.