The mental well-being of youth is influenced by life events, which affects mental health in adulthood. Social support has been shown to have a buffering effect on the impact such events may have on mental health. This research aimed to explore the effect social support has on risk factors, such as youth delinquency and discrimination from private individuals and authorities and how these influence mental well-being. Drawing on data from a study of Norwegian youth and young adults (n = 2588), gender, trust in others and parents’ background positively influenced mental well-being. Use of alcohol, cannabis and experiences of discrimination negatively influenced mental well-being. Social support moderated these negative effects to various degrees. The findings can be applied to targeted social work interventions aiming to strengthen youths’ well-being and ability to cope with life struggles. Social workers have a strong ally in the youths’ network, and the youths themselves should be key players in selecting their supporters.