To make an outside air introduction distance short as much as possible to efficiently introduce outside air through a filter from a radiator suction side by providing the filter on an outside air inlet formed on a partition wall itself.

A revolving work machine includes: an engine 3 and a suction type radiator 4 provided on the rear of a revolving frame 2; a bonnet 6 covering the engine 3 and the radiator 4 to form an engine room 5; and a cabin 7 provided in front of the engine room 5. Between the cabin 7 and the engine room 5, a partition wall 8 forming the front part of the bonnet 6 is vertically arranged from the revolving frame 2. An air conditioner body 10 is provided in front of the partition wall 8 and in the lower part of the cabin 7. An outside air inlet 11 of the air conditioner body 10 is formed on the part of the partition wall 8 which faces a radiator suction space S, and a filter 12 is provided on the outside air inlet 11.