The Silver Linings Playbook star was unable to accept her 'Best Actress' award at this weekend's Australian Academy of Cinema and Television Awards in Los Angeles, Metro reports.
Her co-star Jacki Weaver collected the award on behalf of the star before revealing that Lawrence is ill with pneumonia.
Weaver explained: "I'm going to receive this on her behalf. Poor Jen is really sick. She really is sick. She has pneumonia."
The film's producer also commented that the Hunger Games actress has not had "enough bed rest" with her recent commitments.
Silver Linings Playbook is nominated for a total of eight Academy Awards, with Lawrence up for the 'Lead Actress' prize.
Co-stars Bradley Cooper, Robert De Niro and Weaver have also received nominations in their respective categories. It is the first film in 31 years to receive nominations in all four acting categories.
Lawrence was also unwell with flu when she appeared at this month's Golden Globes on January 13.
The 22-year-old star is currently the odds-on favourite to win the Academy Award against competition from Zero Dark Thirty's Jessica Chastain and The Impossible's Naomi Watts.
Take a look back at Jennifer Lawrence's career in pictures below: