A hybrid vehicle, an air conditioning system and a method for controlling the air conditioning system are provided. The air conditioning system includes: an electric compressor; a mechanical compressor, connected with the electric compressor in parallel; a power battery, connected with the electric compressor and configured to supply power to the electric compressor; an engine, connected with the mechanical compressor and configured to supply a power source to the mechanical compressor; an engine controller, connected with the engine and configured to start the engine when the mechanical compressor is to be started; a battery manager, connected with the power battery and configured to detect a state of charge of the power battery; and a controller, connected with the engine controller and the battery manager and configured to start the electric compressor and the mechanical compressor at different time according to the state of charge of the power battery.