To provide an engine-driven air conditioner, in which environmental temperature around a vibration isolator installed in a machine room is reduced.

In the machine room 5 of the air conditioner, an engine 6 for driving a compressor 7 is mounted through a vibration isolator 34 on a support 28 erected on a base frame 21, and the whole equipment is covered with an external panel 12. The air conditioner is equipped with cooling means 24, 29, in which outside air is introduced from the outside of the panel 12, and the outside air is conducted through an air passage 29 formed in the support 28 to the vibration isolator 34.