The billboards depict Curtis "50 Cent (search)" Jackson holding a gun in his left hand and a microphone in his right. One of the advertisements is next to a preschool.
Najee Ali, who organized a rally Tuesday, accused Paramount of irresponsibility for marketing in high-crime areas a movie that he said glorifies carrying guns.
"We're calling upon Paramount Pictures to remove these billboards out of our neighborhood and from this city," Ali said.
A Paramount spokeswoman did not immediately return a message left at her office before business hours Wednesday.
"Get Rich or Die Tryin'" stars Jackson as a drug dealer who turns away from crime to pursue his true passion, rap music. It's scheduled to open Nov. 9.