Purpose: To describe and explain variations in first mental health service utilization before and after running away from home for homeless adolescents. <br/>Methods: Survey interviews were conducted with homeless and runaway youth in several Midwestern locations. The effects of family of origin factors and street experiences on the likelihood of seeing a mental health professional for the first time before running away and after running away for the first time were examined. Bivariate and multivariate logistic regression methods are used to analyze these data. Interactions are tested across race and gender sub-groups. <br/>Results: Caretaker education, caretaker rejection, and family transitions increase the probability that an adolescent first sees a mental health professional before running away from home. Post-run intervention is more likely for females, younger runaways, shelter users, youths with social support networks, and youths abused by their caretakers. A gender gap in first service use exists for Whites but not for minority youth. Minority youth who experienced family abuse were less likely than abused Whites to report ever seeing a mental health professional. <br/>Conclusions: Analyses indicate homeless youth’s utilization patterns are differentiated by family of origin factors, street experiences, timing of first utilization, and by race and gender interactions. Our findings suggest that youths whose first contact with mental health service use follows running away for the first time may experience higher levels of mental distress compared with other homeless runaways. The significant differences in first service use across race and gender subgroups should be further explored. The racial-ethnic gap in first mental health intervention for abused youths indicates this sub-group is not receiving services that are available to other homeless youths. Our findings suggest that homelessness does not homogenize racial/ethnic differences in first mental health service utilization. (Authors)