Swiveling work machine having a mechanism for introducing ambient air to an air conditioner main body

A swiveling work machine includes: a swivel deck (2); an engine (3) disposed rearward of the swivel deck (2); a suction type radiator (4) disposed rearward of the swivel deck (2); a bonnet (6) covering the engine (3) and the radiator (4) and forming an engine room (5); a cabin (7) disposed frontward of the engine room (5); a partition wall (8) standing on the swivel deck (2) between the cabin (7) and the engine room (5) and forming a front portion of the bonnet (6); an air conditioner main body (10) disposed frontward of the partition wall (8) and in a lower portion of the cabin (7); an ambient air inlet (11) for supplying ambient air to the air conditioner main body (10), the ambient air inlet (11) being formed in a portion of the partition wall (8) facing a radiator suction space (S); and a filter (12) provided in the ambient air inlet (11).