Although there is no more enduring Hollywood star or icon of the film industry than Marilyn, she never received an Academy Award in recognition of her talent, either in her own lifetime or posthumously. Recognition was more forthcoming from other countries (France and Italy) than from her own.
The closest Marilyn ever got to an Oscar was in 1951, a year before she had graduated to top-star billing, when she went to the Pantages Theater (6233 Hollywood Boulevard, Hollywood) to present the Best Achievement in Sound Oscar to Thomas Moulton for his work in ALL ABOUT EVE (1950). For the occasion she looked resplendent in a off-the-shoulder gown borrowed from the Fox wardrobe department. There was drama just before she was due to go on stage, when she noticed a small rip in the dress. A bevy of Fox handlers had to fix the rip ad calm her nerves sufficiently for her to conquer her stage fright.
The closest Marilyn came to winning on her own merits was rumors of a Best Actress nomination for her performance in BUS STOP (1956), and then two years later for SOME LIKE IT HOT (1959). On neither occasion did the nomination materialize; the Oscars going in 1956 to Ingrid Bergman (Anastasia) and in 1959 to Simone Signoret (Room at the Top). Her co-star Don Murray was nominated for his role in BUS STOP. On two separate occasions, film columists have suggested giving Marilyn a special posthumous career Oscar, first in 1963, then ten years later.
-from The Marilyn Encyclopedia by Adam Victor
Footage from Marilyn’s appearance at the 1951 awards does exist. A 2 second clip was shown in a compilation of presenters shown on the awards in the 1980’s.
The Franklin Mint even commemorated this event with a doll in 2007.