To provide an air-conditioning system for a double-deck elevator capable of effectively utilizing a space at a periphery of a car by reducing the number of indoor units and outdoor units.

The air-conditioning system 30 for the double-deck elevator having an upper car 1b and a lower car 1a is provided with: one first air conditioner 2 provided on the lower car 1a; and one second air conditioner 3 provided on the lower car 1a and connected to the first air conditioner 2. A blasting direction changing duct (branch part) 18 is connected to the first air conditioner 2 out of them. Blasting from the first air conditioner 2 is branched by the blasting direction changing duct 18, and air is fed into the upper car 1b and the lower car 1a, respectively.