While youths are increasingly diagnosed with serious psychiatric disorders, little is known about how they conceptualize their own problems or the impact of mental illness labels on their psychological well-being. These are matters of great concern because of the potential vulnerability of young people to stigma as well as the fact that fear of labels or anticipation of stigma are common barriers to adolescents' ongoing mental health service utilization. This study uses mixed-method interviews with 54 US adolescents receiving integrated mental health services in a mid-sized mid-Western city to examine: (1) the extent to which they use psychiatric terms to refer to their problems ("self-label"), and (2) the relationships between adolescents' self-labeling and indicators of psychological well-being (self-esteem, mastery, depression and self-stigma). Associations between self-labeling and perceived negative treatment by others (public-stigma), clinical and demographic factors are explored to identify which adolescents are more likely to self-label. Based on Modified Labeling Theory [Link, B., Cullen, F., & Struening, E. (1989). A modified labeling theory approach to mental disorders: An empirical assessment. American Sociological Review, 54(3), 400-423.] and Thoits's [(1985). Self-labeling processes in mental illness: The role of emotional deviance. American Journal of Sociology, 91(2), 221-249.] work on self-labeling, it was expected that many youth would not self-label and that self-labelers would demonstrate poorer psychological well-being. As expected, the findings indicated that only a minority of adolescents 'self-labeled'. Most conceptualized their problems in non-pathological terms or demonstrated uncertainty or confusion about the nature of their problems. Adolescent who self-labeled reported higher ratings on self-stigma and depression, and a trend toward a lower sense of mastery, but there was no association with self-esteem. Certain characteristics and experiences were correlated with a greater propensity to self-label including: more perceived public-stigma, younger age at initiation of treatment, and higher socio-economic status. This work contributes to knowledge about the variation of adolescents' experiences with stigmatizing labels and their impacts.