BACKGROUND: Sexual minority young people have demonstrated higher rates of emotional distress and suicidality in comparison to heterosexual peers. Research to date has not examined trends in these disparities, specifically, whether there have been disparity reductions or increases and how outcomes have differed over time by sex and sexual orientation group. METHODS: Minnesota Student Survey data, collected from 9th and 12th graders in 3 cohorts (1998, 2004, 2010) were used to examine emotional distress and suicidality rates. Logistic regression analyses were completed to examine outcome changes over time within and across sexual orientation/sex groups. RESULTS: With few exceptions, sexual minority youth are at increased risk of endorsing emotional distress and suicidality indicators in each surveyed year between 1998 and 2010. Young people with both-sex partners reported more emotional distress across all health indicators compared to their opposite-sex partnered peers. With a few exceptions, gaps in disparities between heterosexual and sexual minority have not changed from 2004 to 2010. CONCLUSIONS: Disparities in emotional health persist among youth. Research is needed to advance understanding of mental health disparities, with consideration of sexual orientation differences and contextualized to sociocultural status and changes over time. Personalized prevention strategies are needed to promote adolescent mental health.