A wheel loader includes: a mechanical drive unit; a mechanical drive clutch (43, 47) controlling transmission/cutoff of a power in the mechanical drive unit; an HST pump (22) driven by an engine; a hydraulic motor (23, 24) driven by a hydraulic oil delivered from the HST pump (22); a hydraulic drive unit; a hydraulic drive clutch (54, 65) controlling transmission/cutoff of a power in the hydraulic drive unit; a load detecting unit (101) detecting an amount of a load; a vehicle speed sensor (116) detecting a vehicle speed; a switching controlling unit (102) setting a switching vehicle speed in accordance with the amount of the load; and a vehicle-body controller (100) switching between mechanical drive state and hydraulic drive state based on the switching controlling unit (102). The switching controlling unit (102) sets the switching vehicle speed at a high-speed side when the load becomes large and at a low-speed side when the load becomes small.
