Research on the risk factors associated with gang joining suggests that the best predictor of gang membership is the accumulation of risk factors across a number of domains. These same risk factors are also associated with poor mental health and suicide, suggesting that gang members may be at risk for these outcomes. The current study utilized a nationally representative sample to examine two related issues. First, do youth who later become gang involved report levels of self-esteem, depression, suicidal thoughts, and attempted suicide that are substantively different than the general population? Second, how does gang membership affect these indicators of mental health? Results suggest that youth who become gang involved have significantly higher levels of depression and report a substantively higher rate of suicidal thoughts and behaviors than comparison youth. Furthermore, membership in gangs exacerbates these underlying problems, creating higher levels of depression and a higher prevalence of suicidal thoughts and actions.