Washington, who won the 2010 Tony Award for his performance in August Wilson's Fences, stars as Walter Lee Younger opposite film, television and stage actress LaTanya Richardson Jackson as Lena Younger.
Tony Award-winning actress Diahann Carroll was to return to Broadway in Raisin, but withdrew from the production due to the demands of the rehearsal and performance schedule. Richardson Jackson was called upon by director Kenny Leon to step in.
The production, directed by Tony Award nominee Leon, began performances March 8 for a 14-week limited engagement through June 15.
Okonedo is appearing with the permission of Actors' Equity Association.
Originally produced in 1959, Hansberry's A Raisin in the Sun was the first play written by an African American woman to be produced on Broadway, where it won the New York Drama Critics Circle Award for Best Play.
Here's how producer Scott Rudin bills the work: "Set on Chicago's South Side, A Raisin in the Sun revolves around the divergent dreams and conflicts within three generations of the Younger family: son Walter Lee (Washington), his wife Ruth (Okonedo), his sister Beneatha (Rose), his son Travis and matriarch Lena, called Mama (Carroll). When her deceased husband's money comes through, Mama dreams of moving to a new home and a better neighborhood in Chicago. Walter Lee, a chauffeur, has other plans: buying a liquor store and being his own man. Beneatha dreams of medical school. The tensions and prejudice they face form this seminal American drama."
Other members of the creative team include scenic designer Mark Thompson, costume designer Ann Roth, sound designer Scott Lehrer and lighting designer Brian MacDevitt.
The classic Hansberry drama was last seen on Broadway in 2004 starring Sean Combs.
Washington has also been seen on Broadway in Julius Caesar and Checkmates.