The writer’s work tells the story of a Nigerian woman who moves to the US to pursue a college education.
In 2008, her second novel, Half of a Yellow Sun, won the UK’s Orange Prize and Purple Hibiscus was long listed for the Booker Prize four years earlier.
Other category winners for the US honor included Sheri Fink’s book about Hurricane Katrina.
Her account of the patients, staff and families who took shelter in New Orleans’ Memorial Hospital during the devastating storm took the non-fiction prize.
Frank Bidart won the poetry section for his collection Metaphysical Dog, while Amy Wilentz was honored with the autobiography award for her account of journeys to Haiti following the 2010 earthquake in the country.