The actress, who was 91 years old, died on Wednesday night in New Rochelle, New York, surrounded by her family.
"She died of natural causes," said Arminda Thomas, who works for Dee's family. "She was blessed with old age."
The petite actress won an Oscar nomination in 2008 for her role in "American Gangster." After being nominated for six Emmys, she won the award in 1991 for her role in the TV movie "Decoration Day."
Dee was married to actor Ossie Davis for 56 years until his death in 2005. The couple formed an exceptionally productive and enduring artistic and activist partnership. They performed together in 11 plays and five films and appeared together at some of the seminal events of the turbulent civil rights era.
The actress broke free from the racially stereotypical roles often given to black actresses when she began her career in the 1940s and continued to act into her 90s.
During her pioneering seven-decade career, she won plaudits on Broadway and in her two dozen films.