WORKING MACHINE WITH A CVT

In a working machine including a belt-type continuously variable transmission, a working rotational speed of a working unit can be optionally adjusted, and stable work by the working unit is performed. A working machine 10 having a belt-type continuously variable transmission 63 in a working power transmission system 31, includes a target working speed setting section 147 for optionally setting a target working rotational speed Bs of a working unit 14, a working unit speed sensor 76 that detects an actual working rotational speed Br of the working unit, a speed reduction ratio regulation mechanism 90 that regulates a minimum speed reduction ratio of a rotational speed of a driven pulley 74 with respect to a drive pulley 72, and a control unit 43. The control unit controls a rotational speed Er of the drive source so as to bring the actual working rotational speed close to the target working rotational speed, obtains a minimum limit speed reduction ratio Ram on the basis of a target minimum rotational speed Em of a drive source 13 which is set in advance or set by the drive minimum speed setting section 142, and the target working rotational speed, and controls the speed reduction ratio regulation mechanism to keep the minimum limit speed reduction ratio.