Severe economic crisis has contributed to the rise in the incidence of child labour in Nigerian cities. For many hours a day, children are engaged in economic tasks (paid and unpaid for), which are detrimental to their physical, mental, social and moral well-being. For these children, involvement in child labour has limited their social relevance to the immediate and larger society. The main objective of this study therefore, is to examine the social implications of child labour on children in selected Nigerian cities. The specific objectives of the study include: (i) assess the incidence of child labour in the Nigerian cities, (ii) examine the implications of child labour on children’s education, health and delinquent behaviour. The study adopts survey research method in which relevant data were collected through administered questionnaire to respondents. The respondents were selected from three cities in Nigeria namely; Ibadan, Enugu, and Kaduna. The cities were selected based on their strategic importance as former administrative centres of the three old regions of Nigeria. Some of these areas were chosen randomly in each city and a total of 826 child labourers were selected as respondents using judgemental sampling method. Chi-square was used to determine the relationship between the type of child labour engaged in and respondents’ social characteristics. Findings from the study revealed that: (i) child labour activities fall into different categories namely, bus conducting, car washing, hawking, begging and others such as weaving, tailoring, hairdressing and auto-repairing, (ii) most children who engage in child labour are largely from the lower economic stratum of the society; (iv) incidence of child labour was also significantly related to the rate of child’s health status (r = 0.21> t0.05); school attendance (r = -0.62 > t0.05); academic performance (r =0.39 > t0.05) their delinquent behaviours (r =0.57 > t0.05);contact with parent (r = 0.24 > t0.05) and child’s exploitation by employers (r= 0.31 > t0.05). In conclusion, children who engage in economic activities are found to be different with respect to their social development. It is therefore recommended that: (i) strict measure should be taken by appropriate authorities to curtail employers from engaging under-aged children in hazardous jobs that can impair their health status and hinder their educational development; (ii) there should be public enlightenment programmes, targeted at the poor section of the population, on the negative implications of child labour to the victims (the children), the family and the society at large; and (iii) efforts should be made to embark on realistic and practicable poverty alleviation programmes aimed at reducing the incidence of poverty among Nigerians which was found to be a major cause of child labour.