Officials say the man, shown wearing a bright yellow traffic vest, robbed the TCF Bank branch at 7910 S. Cicero Ave.
They say he implied that he had a weapon, but no such weapon was shown.
The suspect is described as a black male, with brown hair and a thin mustache. He wore a gray hooded sweatshirt underneath the yellow vest.
Anyone with information about the robbery is asked to contact the FBI Chicago office at (312) 421-6700.
The Sun-Times Media Wire contributed to this report.