Sri Lanka is an island country located in the Indian Ocean, characterized by tropical weather, with an estimated population of 21.4 million in 2017, one third of them being children. Advancing and rapidly changing technology, novel industries, consumer goods and equipment have introduced new health hazards of a chemical, biological and physical nature to future generations. The infant mortality rate has declined to around 8–9 per 100,000 since 2015. Congenital malformations were the most significant cause of neonatal death. Thus, there might be unproven environmental factors which affect infant mortality rates despite robust field and hospital services. Air pollution is a major environmental health hazard to children, largely due to hazardous industries, vehicular emissions and traditional cooking stoves. The health of children living in urban households and attending schools in cities is adversely affected by air pollution. Usage of polythene and plastic for toys, utensils, bags, lunch sheets and other daily essentials leads to overusage and improper waste management and open burning. This emits dioxins, which are carcinogens, hormone disruptors, and which can be transferred to the fetus via the placenta. In rural areas, the burning of agricultural waste and certain agro-forestry activities have also led to air pollution. Indoor air pollution (IAP) remains a large threat as 66% of the population use biomass for cooking. Use of inefficient stoves and biomass, poor ventilation and absence of chimneys, contribute to IAP. Other indoor air pollutants such as tobacco smoke, volatile organic compounds, asbestos, pesticides, kerosene, mercury, mosquito coils and biological pollutants also prevail. Biological pollutants, such as dust mites, droppings and urine from pets, insects and rodents, pollen from indoor plants and outdoor air, and fungi, including moulds in poorly maintained buildings, can trigger asthma or cause allergic reactions and infections among children inhabiting these environments. In rural areas, chemicals were accountable for 30.2% of acute poisonings, with kerosene oil being the most common cause, followed by paracetamol. More than 80% of agricultural workers in the country work in the informal sector with limited personal protective equipment use, while pesticide usage is increasing. Children who engage in agriculture-related work and hazardous industries are at risk of developing health consequences at early stages. Dengue remains a major environmental health problem as the reduction of mosquito breeding sites has been a challenging task for many years. It is essential to gain more evidence of existing environmental risk factors and their associations with the health of children. Information dissemination among local and international experts on Children’s Environmental Health (CEH) issues needs to be enhanced and properly established. Training programs should be conducted for healthcare workers to update their knowledge. Pediatricians are needed for remote hospitals and primary healthcare centers. Environmental parameters and biological parameters are not routinely monitored in most of the hazardous environments.