"Lion," which is already receiving critical acclaim, is based on the true story of Saroo Brierley, a young Indian boy who gets separated from his brother and mother when he ends up 1,000 miles away from his home, lost at a train station in Kolkata.
Patel, who made his foray into films with 2008's "Slumdog Millionaire," stars as an older Saroo, who gets adopted by a woman in Australia.
The 26-year-old actor said that his mother was the reason he took the role in the Weinstein Co. Production, for which he spent eight months preparing.
"The greatest influence in my life has been my own mother, so when I read this, I knew I was gonna do this film for her," Patel said.
In "Lion," the actor's on-screen adoptive mother is played by Nicole Kidman, and his Indian mother is played by Priyanka Bose.
Directed by Garth Davis, the film hits theaters on November 25.