Gambling disorder is associated with suicidal behaviors, but it is not clear whether the association is due to common etiologic factors or to gambling disorder being causally related to suicidality. This question was examined from the perspective of epidemiologic, longitudinal, and discordant-twin studies. The results suggested that the causes of the association with disordered gambling differed for suicidal ideation, plan, and attempt and differed for men and women. The association of suicidal thoughts with disordered gambling was noncausally explained by common genetic influences among women but not men. Conversely, there was evidence consistent with a potentially causal influence of disordered gambling on suicide attempt among men but not women, which might have been related to gambling-related financial problems. The use of monetary data to identify individuals experiencing financial harms associated with their gambling may represent a more practicable target for screening, intervention, and prevention and may reduce gambling-related financial crises, thereby warding off a potential gambling-related suicide attempt.