To evaluate whether anti-bullying policies that are inclusive of sexual orientation are associated with a reduced prevalence of suicide attempts among lesbian, gay, and bisexual youths. A total of 31,852 11th-grade public school students (1,413 lesbian, gay, and bisexual individuals; 4.4%) in Oregon completed the Oregon Healthy Teens survey in 2006-2008. The independent variable was the proportion of school districts in the 34 counties participating in the Oregon Healthy Teens survey that adopted anti-bullying policies inclusive of sexual orientation. The outcome measure was any self-reported suicide attempt in the past 12 months. We stratified results by sexual orientation.Lesbian and gay youths living in counties with fewer school districts with inclusive anti-bullying policies were 2.25 times (95% confidence interval [CI], 1.13-4.49) more likely to have attempted suicide in the past year compared with those living in counties where more districts had these policies. Inclusive anti-bullying policies were significantly associated with a reduced risk for suicide attempts among lesbian and gay youths, even after controlling for sociodemographic characteristics (sex, race/ethnicity) and exposure to peer victimization (odds ratio, .18; 95% CI, .03-.92). In contrast, anti-bullying policies that did not include sexual orientation were not associated with lower suicide attempts among lesbian and gay youths (odds ratio, .38; 95% CI, .02-7.33).Inclusive anti-bullying policies may exert protective effects for the mental health of lesbian and gay youths, including reducing their risk for suicide attempts.