Between 1990 and 2009, the annual number of deaths among children younger than 5 fell from 12.4 million to 8.1 million, UNICEF said in a news release issued from New York.
"The good news is that these estimates suggest that 12,000 fewer children are dying each day around the world compared to 1990," the organization said.
However, "the tragedy of preventable child deaths continues," the organization said.
About 22,000 children under the age of 5 die every day, with 70 percent of these deaths occurring within the first year of life, UNICEF said.
Under-5 mortality is becoming more concentrated among just a few countries, with nearly half of all deaths in this age group occurring in India, Nigeria, the Democratic Republic of the Congo, Pakistan and China last year, the non-government organization said.