Slum comprised of unhygienic sanitation, contaminated water, open sewerage, and inadequate solid waste management. Consequently, they are experienced to have negative impact on children’s physical health and cognitive abilities. The current is an attempted to examine the impact of slums on children’s health by comparing than with the children living in non-slum (but otherwise similar) area. For this purpose, data was collected from two areas Muslim colony (slum or treated group) and Bari imam (the controlled group). The results Show that exposure inadequate conditions in slum have adversely affected the height for age Z (HAZ) score of children. The main channel for this impact is diarrhea. Interestingly, the link between slum environment and children’s cognitive ability variables. Once we control for parents characteristics, especially parents education. Supervisor:- Dr. Muhammad Nasir