A walk-behind work machine in which vibration produced by the driving of an engine is not readily transmitted to an operating handle. The work machine includes a work-machine body (11) having a plurality of mounting parts (31 - 34) to which an engine (15) is joined. The mounting parts include a high-rigidity mounting part (31) positioned at a maximally rigid part (24) on the work-machine body, and other mounting parts (32 - 34) exclusive of the high-rigidity mounting part. The engine is joined securely to the other mounting parts and is joined more loosely to the high-rigidity mounting part than to the other mounting parts. (FIG. 2)
