The West Hollywood City Council voted unanimously Monday to outlaw the declawing of cats.
The ban, which will take effect in 30 days, will affect all three of the city's veterinary clinics.
Only one person spoke against the ban, which was proposed by Councilman John Duran.
Although declawing is illegal in several European nations, animal advocates said they know of no such restrictions in the United States.
An aide to Duran said the new law "goes along with Councilman Duran's philosophy and the city's philosophy that animals are not property."
West Hollywood already has a law designating its residents as pet guardians rather than pet owners.
Some veterinarians say declawing of cats is important when an owner has a compromised immune system.