The two-time Oscar winner (once for best actress, once for best original song) will perform in a to-be-determined capacity on the Feb. 24 show, joining previously announced performers Adele and Norah Jones.
"In an evening that celebrates the artistry of movies and music," said producers Craig Zadan and Neil Meron, "how could the telecast be complete without Barbra Streisand? We are honored that she has agreed to do a very special performance on this year's Oscars, her first time singing on the show in 36 years."
Streisand won her first Oscar, for best actress, for her performance in "Funny Girl" (1968), and she was nominated again in 1973 for her lead performance in "The Way We Were." In 1976, she and Paul Williams won the Oscar for best original song for the love theme to "A Star Is Born." She was later nominated for producing the best picture nominee "The Prince of Tides" (1991), which she also directed, and for co-writing the original song "I Finally Found Someone" from "The Mirror Has Two Faces" (1996).