The high court ruling affirmed the right of individuals to keep guns for self protection.
Two years ago, the Supreme Court handed down a similar ruling that applied only to federal laws.
Monday's decision extends that judgment to state and local government laws.
The case now goes back to the 7th Circuit Court of Appeals, and it could be several months before the case is decided.
Meanwhile, the city is working on new ordinances which have gun ownership restrictions.
New regulations could include gun registration fees, laws prohibiting assault weapons, and a possible requirement that gun owners buy liability insurance.
In the meantime, the city is reminding people that until that happens or a new ordinance is passed, Chicago's handgun ban remains in effect.