Research suggests sex-related substance use can be conceptualized within the disinhibited externalizing spectrum of psychopathology. However, this research has generally excluded sexual-minority samples. In the current study, we examined the associations between the disinhibited externalizing spectrum and several sex-related substance use domains (i.e., heavy drinking and poppers [alkyl nitrite], cannabis, cocaine, and methamphetamine use) in a clinical sample ( N = 254) of sexual-minority men. Disinhibited externalizing was significantly associated with reporting sex-related cannabis and methamphetamine use versus not and with frequency of sex-related alcohol and cocaine use. These results suggest few and generally weak associations—except for methamphetamine use—between the disinhibited externalizing spectrum and sex-related substance use. Implications for the applicability of dimensional models of psychopathology for sexual-minority populations, future directions for research on sexual behavior and substance use grounded in the specific sociocultural context in which sexual-minority men exist, and transdiagnostic interventions for sex-related substance use are discussed.