PURPOSE: To provide a car airconditioning device capable of cooling the fresh outer air whose temp. has risen through adiabatic compression.

CONSTITUTION: An airconditioner for car which is installed in the roof part 2 of a car 1, is configured with the outdoor part 5 having an outdoor heat exchanger 8 and an outdoor blower 7 and the indoor part 6 having an indoor heat exchanger 13 and indoor blower 11 and installed adjacent to the outdoor part where one end is punt in communication with the indoor part 6. The arrangement includes a cooling duct 31 located where the air stream generated with the operation of the outdoor blower 7 runs against, a fresh outer air duct 15 whose one end is connected with the other end of the duct 31, and an outer air introducing blower 16 which is installed at the other end of this fresh outer air duct 15 and introduces the fresh outer air into the indoor part 6 via the ducts 15, 31.