Child labor is a worldwide phenomenon, but more focus is required on developing countries, like Bangladesh. Most of us consider child labor exploitative and socially unacceptable. The study of child labor is, however, important not only for physical and psychological, but also for economic ones. In Bangladesh, working children are comfortable to running in industrial, mechanized, small scale factories, metal works, constructions, and hotels, also in several informal segment activities. An important effect of child labor is on demographic development. It is generally found that poor countries with high rates of population growth have higher incident of child work. Child labor constitutes an important obstacle to achieving Universal Primary Education and other Millennium Development Goals in Bangladesh. It not only harms the welfare of individual children, but also slows broader national poverty reduction and development efforts. They also suffer from breathing problems, physical pain, eye sight problem, cold and fever, minor injuries and skin diseases. The main purpose of this work is to make us keep in mind that all of them are children and all of them want to lead a happy life.