Objective: This study examined rates of self-harm and suicidality (ideation and behavior) in children referred clinically for gender dysphoria compared with their siblings, and referred and nonreferred children from the Child Behavior Checklist (CBCL) standardization sample. Predictors or correlates of self-harm/suicidality were also examined. Method: The sample consisted of 572 gender-referred children, 425 siblings, 878 referred children, and 903 nonreferred children. Parent report for 2 CBCL items was used to assess self-harm and suicidality. CBCL total behavior problems and a metric of peer relationship problems were also used. Results: The gender-referred children and the referred children from the standardization sample had significantly higher scores than siblings and nonreferred children in terms of self-harm/suicidality, total behavior problems, and poor peer relations. Based on logistic regression analyses, gender-referred children were 5.1 times more likely than nonreferred children to talk about suicide and 8.6 times more likely to self-harm/attempt suicide, even after overall behavior problems and peer relationship problems were accounted for. In the final models, group, older age, and more total behavior problems, but not poor peer relations, were significantly associated with an increased likelihood of self-harm/suicidality. Conclusion: By parent report, children with gender dysphoria show an increased rate of self-harm/suicidality as they get older. This risk was not simply an artifact of the presence of behavioral and emotional problems, although these problems were significant correlates of self-harm/suicidality. Clinicians should routinely screen for the presence of suicidal ideation and behavior in children with gender dysphoria, particularly during the second half of childhood.