PURPOSE: To provide a cooling and heating device for a vehicle for cooling and heating a local part of the vehicle stably without using a special heat source.

CONSTITUTION: A seat air conditioning circuit 6 having a water duct 16 and a cooling medium duct 15 for circulating coolant 7 between the water duct 16 of a main heat exchanger 3 disposed in a ventilation duct 2 connected with a vehicle chamber 1 and an auxiliary heat exchanger mounted under a driver's seat 4, a cooling medium circuit for freezing operation of cooling medium 9 to the cooling medium duct 15, and a hot water circuit 10 for sending the coolant 7 heated by waste heat of a water cooling mounted engine 28 to the seat air conditioning circuit 6 for achieving heating operation are provided.