Heat pump has been applied to electric buses to improve power efficiency. The heating system of electric buses generally consists of roof-on mount type heat pump and an electric heater mounted on the floor. These two heating systems are independently operated and controlled. It should be noted that the application of independent control heat pump was not effective in improving power consumption as a result of survey. Cooperative heating control maximizes the operation duty of the heat pump without additional attention or manipulation of the driver on field driving. It has been developed and applied to our EV bus applied roof-on mount heat pump system.