Child labour is one of the most important social harm in the world. Many children are working in exploitative conditions and are exploited. In Iran, policies and interventions to eliminate child labour have not been very effective so far. Therefore, considering the diversity and extent of child labour and injuries caused by forced labour on them, the present study has tried to identify the types of child labour in Tehran, categories and occupations of child exploitation and identify the issues and consequences of each type of labour for children; so that through proper knowledge, we can help plan the necessary measures for any child job in order to reduce and eliminate child labour. A qualitative study has used in this research. We used semi-structured, in-depth interviews with 15 key informants in the field of child labour to gather the data. Also, we studied documents which were sampling done intentionally and theoretically. A thematic analysis was used in this study and finally, we reached seven main themes: Workshop work, Peddling, Street services, Barbage gathering, Begging, House working and Delinquencies. In conclusion, results try to get a realistic cognition of child labour based on a holistic approach. We hope this knowledge use as the basis of research and scientific and practical actions of policymakers and institutions in charge of children's health and welfare.