A working machine such as a powered lawn mower has a continuously variable transmission for transmitting the power of an engine to wheels at a variable speed reduction ratio. The continuously variable transmission comprises an axial-plunger-type hydraulic pump disposed in a case for producing a hydraulic pressure, and an axial-plunger-type hydraulic motor disposed in the case for producing a rotary motion in response to the hydraulic pressure supplied from the hydraulic pump. The hydraulic pump has a pump cylinder with a plurality of pump plungers axially movably disposed therein, and the hydraulic motor has a motor cylinder with a plurality of motor plungers axially movably disposed therein. The pump and motor cylinders are disposed closely in juxtaposed relationship in the case and having respective axes that are perpendicular to each other.