The Priyanka Chopra-starrer movie was named the best popular film providing wholesome entertainment.
Film's screenwriter Saiwyn Quadras took to Twitter to express his excitement.
"Yippee to team #MaryKom @priyankachopra @OmungKumar @Vanita_ok @MangteC @OnlerK We won the National Award best film," Quadras posted on Twitter.
The tweet was later retweeted by the biopic's director Omung Kumar, who made his Bollywood debut with the film.
Released last September, the Manipur-set drama also starred Darshan Kumaar and Sunil Thapa in prominent roles.