The 22-year old flipped the bird after taking home the accolade for her leading role in Silver Linings Playbook, as she posed alongside last year's Best Actor winner Jean Dujardin.
It is currently unknown who J-Law was aiming the gesture at, with Digital Spy reporting that it was thought she stuck her middle finger up at a photographer.
However, it seemed The Hunger Games star was just being playful by flipping her middle finger, joking with Dujardin throughout the shoot and telling snappers she was "drunk."
Lawrence was quoted as saying: "I'm sorry, I did a shot before I came out."
She also poked fun at her falling over when accepting her Best Actress award, telling reporters backstage that she "absolutely" tripped up the stairs on purpose.
Jennifer quipped: "What do you mean, 'What happened?' Look at my dress! I tried to walk up stairs in this dress - that's what happened! I think I just stepped on the fabric, and they wax the stairs."
When asked what she was thinking as she fell, J-Law laughed off the mishap and said: "A bad word that I can't say... that starts with 'f'."
The star was later seen attending Vanity Fair's Oscar Party at Sunset Tower in West Hollywood, ditching her flowing white frock for a more practical yet sexy figure-hugging sliver dress.
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