PURPOSE: To provide a rotary hydraulic device in which a plurality of sets of rotors having few pressure teeth engaged with each other and the shafts interlocked with each other are received to discharge fluid of high pressure and large capacity.

CONSTITUTION: A casing 1 consists of a barrel 2, end plates 3 and cover plates 4. The barrel 2 is formed with an inlet 5, an outlet 6 for fluid and a flow path 7 communicating thereto. In the flow path 7 are mounted a plurality of sets of pump members 10, 11, 12, 13 provided with a pair of a drive rotor 8 and a driven rotor 9 having respectively 6 and 4 pressure teeth of so-called herringbone type, which teeth mesh with each other and are formed inclined left and right to the longitudinal axis of the rotor about the mid point of the teeth. The shafts of the rotors 8, 9 are respectively journaled on the end plates 3 through anti-friction bearings 3, 4.