The report, released late today, provides new data on the plight of some 50 million children who have either migrated from their country of birth or been forcibly displaced, many of whom have fled conflicts around the world.
Of the 50 million figure, approximately 28 million children fled violence and insecurity, the report states. About 31 million children live outside their birth countries, and of that number, around 11 million are refugees or asylum seekers.
"While a clear majority of the world's migrants are adults, children now comprise half of all refugees," the report states.
Syria and Afghanistan were responsible for almost half of all child refugees under the mandate of UNHCR, according to the report.
The report states that while the risks that girls and boys face may be different, both sexes are "equally represented" in the population of children registered with the UNHCR as refugees.
Though much focus has been given to migrants and refugees fleeing conflicts in Syria and Northern Africa in recent years, refugees can be found on every continent, according to the report.
"Dramatic increases in the number of children apprehended by immigration authorities at the southern border of the United States reflect underlying challenges for children in their countries of origin," the report states, adding that they "underscore the importance of United States' migration legislation, policy and enforcement decisions for children throughout the region."