To provide a high output type multistage hydraulic device with hydraulic pumps and hydraulic motors integrated for driving a working machine which requires high output for driving a self energy generating hydraulic driven generator, with low output.

A battery 1 is used for a variable speed electric motor B to drive a first hydraulic pump 1 of the high output type multistage hydraulic device A. Thereby, hydraulic pressure is generated, fed to a second hydraulic motor 2 and converted into rotating motion by an impeller 6 to start a second hydraulic pump 3 coaxial therewith (having a discharge amount several times that of the first hydraulic pump). The hydraulic pressure generated by the second hydraulic pump 3 is fed to a third hydraulic motor 4 and hydraulic pressure is similarly generated by a third hydraulic pump 5 coaxial therewith and fed to a final hydraulic motor C to be started, thus permitting the operation of any kind of working machine D. The high output type multistage hydraulic device has fourth hydraulic equipment so on in the same structure.