"I believe Being a brother is bigger than being a Hero. 'Bhaijaan' coming Eid 2015. How do you like the first look?," Shah Rukh tweeted.
The link was later shared by director Kabir Khan on his Twitter page.
A rugged Salman is seen in a brown outfit with a gada (mace)-shaped pendant hanging around his neck in the first look of the movie.
The "Dabangg" star's complete face is not shown in the poster.
The trailer of the film, which recently wrapped up its shooting in Kashmir, is expected to hit tomorrow.
They further cemented their bond when Shah Rukh attended Salman's sister Arpita Khan's wedding last November and posed for a happy picture with brother-sister duo.
The "Happy New Year" star also visited Salman at his residence a day ahead of his hit-and-run verdict.