To provide a hydraulic drive type working vehicle whose hydraulic drive system 1 having a pivotal turning function is constructed one pump two motor type structure.

A pair of front wheels 3A, 3B and a pair of rear wheels 4A, 4B are provided for a vehicle body 2. The front wheels 3A, 3B are interlocked with drive shafts 22A, 22B on the side of hydraulic motors 21A, 21B. One hydraulic pump 30 driven by an engine 25 is provided on the vehicle body 2. Valve means 37A, 37B are interposed in pipe lines 33A, 33B, 34A, 34B to both hydraulic pumps 30 from the hydraulic motors 21A, 21B. The rear wheels 4A, 4B are arranged to the side of vehicle body 2 so as to be rotatable around vertical axes 14A, 14. Pivotal turn is implemented by switching the condition of one of the valve means 37A, 37B to on state, and then feeding pressure oil from the pumps 30 to other ports in both right and left hydraulic motors 21A, 21B so that motors 21A, 21B are rotated reversely mutually.