Adichie, who was born in the city of Enugu, grew up the fifth of six children in an Igbo family in the university town of Nsukka. Nsukka is in southeastern Nigeria, where the University of Nigeria is situated. While she was growing up, her father, James Nwoye Adichie, was a professor of statistics at the university, and her mother, Grace Ifeoma, was the university's first female registrar. Her family's ancestral village is in Abba in Anambra State.
Adichie studied medicine and pharmacy at the University of Nigeria for a year and a half. During this period, she edited The Compass, a magazine run by the university's Catholic medical students. At the age of 19, Adichie left Nigeria for the United States to study communications and political science at Drexel University in Philadelphia. She soon transferred to Eastern Connecticut State University to be near her sister, who had a medical practice in Coventry. She received a bachelor's degree from Eastern, with the distinction of summa cum laude in 2001.
In 2003, she completed a master's degree in creative writing at Johns Hopkins University. In 2008, she received a Master of Arts degree in African studies from Yale University.
Adichie was a Hodder fellow at Princeton University during the 2005–06 academic year. In 2008 she was awarded a MacArthur Fellowship. She has also been awarded a 2011–12 fellowship by the Radcliffe Institute for Advanced Study, Harvard University.
Adichie divides her time between Nigeria, where she teaches writing workshops, and the United States. In 2016, she was conferred an honorary degree - Doctor of Humane letters, honoris causa, by Johns Hopkins University.
She revealed in a 2 July 2016 interview with the Financial Times that she had a baby daughter
Adichie published a collection of poems in 1997 (Decisions) and a play (For Love of Biafra) in 1998. She was shortlisted in 2002 for the Caine Prize for her short story "You in America"
In 2003, her story "That Harmattan Morning" was selected as a joint winner of the BBC Short Story Awards, and she won the O. Henry prize for "The American Embassy". She also won the David T. Wong International Short Story Prize 2002/2003 (PEN Center Award).
Her first novel, Purple Hibiscus (2003), received wide critical acclaim; it was shortlisted for the Orange Prize for Fiction (2004) and was awarded the Commonwealth Writers' Prize for Best First Book (2005).
Her second novel, Half of a Yellow Sun (2006), named after the flag of the short-lived nation of Biafra, is set before and during the Nigerian Civil War. It received the 2007 Orange Prize for Fiction and the Anisfield-Wolf Book Award. Half of a Yellow Sun has been adapted into a film of the same title directed by Biyi Bandele, starring BAFTA winner and Academy Award nominee Chiwetel Ejiofor and BAFTA award-winner Thandie Newton, and was released in 2014.
Her third book, The Thing Around Your Neck (2009), is a collection of twelve dazzling stories that explore the ties that bind men and women, parents and children, Africa and the United States.
In 2010 she was listed among the authors of The New Yorker′s "20 Under 40" Fiction Issue. Adichie's story, "Ceiling", was included in the 2011 edition of The Best American Short Stories.
Her third novel, Americanah (2013), an exploration of a young Nigerian encountering race in America, was selected by the New York Times as one of The 10 Best Books of 2013.
In April 2014, she was named as one of 39 writers aged under 40 in the Hay Festival and Rainbow Book Club project Africa39, celebrating Port Harcourt UNESCO World Book Capital 2014.
In 2015, she was co-curator of the PEN World Voices Festival.
Adichie says on feminism and writing, "I think of myself as a storyteller, but I would not mind at all if someone were to think of me as a feminist writer... I'm very feminist in the way I look at the world, and that world view must somehow be part of my work."[