Movie industry daily Variety said Oscar-winner Roberts had been pencilled in for the role by Paramount Pictures after the studio acquired the screen-rights to Gilbert's acclaimed travelogue.
"Eat, Pray, Love" is Gilbert's account of how she sets out on a year-long journey of self-discovery while travelling through Italy, India and Indonesia following a bout of depression and a contentious divorce.
Brad Pitt will co-produce the movie while Ryan Muphy will adapt and direct, Variety reported.
Variety reported that Gilbert had rebuffed numerous overtures from actresses since the book's publication before signalling her approval to a project spearheaded by Roberts.