The film is a remake of the eponymous 1983 film of the same name.
Salman took to micro-blogging website Twitter to announce the release date alongside a poster of the film featuring Sooraj Pancholi.
"Back off, HERO coming on 4th September @HeroTheFilm," the 49-year-old tweeted.
Sooraj is the son of Aditya Pancholi and Zarina Wahab, while leading lady Athiya is the daughter of Suniel and Mana Shetty.
The first look of the film was unveiled in May this year, which featured the title of the movie and the words -- "Love. Rebels. Freedom".
"Hero" was originally directed and produced by Ghai, with Jackie Shroff and Meenakshi Sheshadri leading the cast.
The remake is directed by Nikhil Advani, and it also stars Govinda, Anita Hassanandani, Vinod Khanna and Kader Khan as the supporting cast members.
