Directed by Xu Ang, "12 Citizens" beat 15 other films and won the Cinema d'Oggi section or Cinema Today's People's Choice Award, which was announced at the end of the Rome Film Festival, China Daily reported.
Aside from that, the legal drama inspired by 1957 Hollywood film "12 Angry Men" was also the only Chinese-language film competing for one of the top awards of the festival.
"The diversity of these characters represents my personal understanding of China, or to be more specific, of Beijing," said Xu, who based the 12 main characters of the story of "12 Citizens" on his real-life experiences.
"These12 people are based on people I have met. So, the discrimination, conflict and argument in the film are probably real things I have experienced," the Chinese director explained.
Written by Xu with Han Jinglong and Li Yujiao, the story of "12 Citizens" revolves around a virtual courtroom of 12 men deliberating over a case involving a young man adopted by a wealthy family who murdered his birth father.
The 12 main characters in the film were played by Wang Gang, He Bing, Han Tongsheng, Liu Hui, Li Guangfu, Mi Tiezeng, Zhang Yongqiang, Gao Dongping, Qian Bo, Zhao Chunyang, Lei Jia and Ban Zan.
Aside from "12 Citizens," another big winner in the Rome Film Festival is the Brazilian-English produced movie "Trash" directed by British filmmaker Stephen Daldry.
Written by Richard Curtis, "Trash" is about three boys in Rio de Janeiro who discovered a politician's wallet in a garbage dump that reveals mass corruption.
The film was based on Andy Mulligan's novel, which was shortlisted for the BBC Blue Peter Book Awards in 2010, but was disqualified after being regarded unsuitable for younger audience, according to BBC.
"Trash" stars Rooney Mara, Martin Sheen, Wagner Moura, Selton Mello, Christiane Amanpour, Andre Ramiro, Jesuita Barbosa, Rickson Tevez, Daniel Zettel and Maria Eduarda, among others.