US teen author Jacqueline Woodson said it was "awesome" to win The Astrid Lindgren Memorial Award, the world's largest prize for children's writing.
Her books include National Book Prize winner Brown Girl Dreaming, a memoir of her childhood written in verse.
The writer will receive five million Swedish krona ($600,000, £430,000) at a ceremony on 28 May in Stockholm.
Woodson is the 15th recipient of the prize, named after the Swedish creator of Pippi Longstocking.
Brown Girl Dreaming, published in 2014, describes her childhood in South Carolina and New York in the 1960s and '70s, decades marked by civil rights marches, inequality and violence.
Woodson was happy to wake up to the news of her success and shared it on Twitter.
The author was also named National Ambassador for Young People's Literature in the US in January.
She has written more than 30 books in total, most of which focus on teens making the transition from childhood to adult life.
Racism, segregation, economic injustice, social exclusion, prejudice and sexual identity are all recurring themes.
"It's important to hold up mirrors for kids to see their experience is legitimate," she said. "Too often those mirrors aren't there for them."
The Lindgren jury said: "Jacqueline Woodson introduces us to resilient young people fighting to find a place where their lives can take root. In language as light as air, she tells stories of resounding richness and depth.
"Jacqueline Woodson captures a unique poetic note in a daily reality divided between sorrow and hope."
Her other books include The Dear One (1990), about teen pregnancy, and In Beneath a Meth Moon (2012), which tackles drug addiction.