Background Socioeconomic and environmental factors can affect the health of the people living in slums in the suburbs. In these areas, the youth and adolescents are the main age groups susceptible to a multitude of harms such as addiction, AIDS, delinquency, aggressive behavior, and prostitution. The present study was conducted to investigate the state of social harms and social class in Iranian youth and adolescents living in slums in the suburbs. Methods In the present systematic review, the researchers searched for observational and qualitative papers published in Persian or English languages during 2010–2020 timespan in the following databases: Embase, PubMed, Scopus, Web of Science, Irandoc databases, Google Scholar, SID, and Magiran. Based on MESH, the keywords of “social class”, “social harm”, “youth”, “adolescent”, and “slum” were chosen. Papers were assessed according to the inclusion criteria, and the quality of the papers was evaluated using the Newcastle–Ottawa scale for quantitative articles and the COREQ scale for qualitative ones. Results Of 491 articles assessed, 11 (eight cross-sectional and three qualitative papers) were deemed suitable. According to the results, social harms reported were: drug abuse (two studies), female sex workers (two studies), poverty (two studies), AIDS (two studies), social insecurity (two studies), psychedelic substances (one study), alcohol (one study), delinquency (one study), divorce (one study), physical problems (one study), prostitution because of poverty (one study), unemployment (one study), and adolescents’ forced labor due to destitution (one study). Moreover, the assessed papers used education (three studies), economic status (three studies), occupation (two studies), income (two studies), place of residence (two studies), social status (two studies), and cultural status (one study) as indicators of the social class in the individual and their parents, and categorized them in three groups of high (one study), middle (three studies), and low classes (seven studies). Conclusion The present systematic review investigated, for the first time in Iran, social harms and social class in the youth and adolescents living in slums in the suburbs. The results showed that social harm is high among the youth and adolescents in outskirt slums of Iranian cities. Therefore, any attempt to empower the youth and adolescents living in these parts will have direct effects on the health of the residents of these areas.