Often, simple precautionary measures can prevent accidents
More than 800,000 children die each year from burns, car crashes, falls, drowning, poisoning and other accidents, according to a UN report.
Millions more suffer injuries that leave them disabled for life, said the joint report by two UN agencies, Unicef and the World Health Organization.
Most accidents happen in developing countries, with the problem most severe in Africa and South-East Asia.
Simple prevention measures could halve the number of deaths, the report said.
Crashes, drowning, falls
The top five causes of injury and death are road crashes, drowning, burns, falls and poisoning, according to the World Report on Child Injury Prevention 2008.
Top five causes of injury death
Road crashes: 260,000 children a year
Drowning: 175,000 children a year
Burns: 96,000 children a year
Falls: 47,000 children a year
Poisoning: 45,000 children each year
Road crashes kill 260,000 children a year, injure about 10 million and are the leading cause of death among 10-19 year olds.
About 175,000 children die through drowning every year.
Fire-related burns kill nearly 96,000 children a year, while nearly 47,000 children fall to their deaths every year and more than 45,000 die from unintended poisoning.
"Unintentional injuries are the leading cause of childhood death after the age of nine years and 95% of these child injuries occur in developing countries," said Ann Veneman, Unicef executive director.
"More must be done to prevent such harm to children."
Urgent action is needed, the organisations said.
"The price of failure is high," Margaret Chan, director general of the WHO, added.
"On current estimates, unintentional injuries claim the lives of around 830,000 children worldwide every year."
Africa has the highest rate for unintentional injury deaths.
Its rate is 10 times higher than that in higher-income countries in Europe, which have the lowest rates of child injury.
But accident-related deaths still account for 40% of all child deaths in developed countries.
Better emergency medical care and rehabilitation services would help, the report said, as would the redesign of toys and playground equipment.
Using seatbelts and helmets, fencing in pools and water, and using child-safe medicine bottles could reduce the rate of accidents, it added.