The invention provides a hydraulic system of a stepless speed regulation hydropress, belongs to the hydraulic system of a hydropress, and solves the problems that an existing deviation-rectifying synchronous control system is not high in control precision and has a bad capability of resisting unbalance loading. The hydraulic system comprises a first hydraulic cylinder, a second hydraulic cylinder, a sliding block, a first flow pump, a second flow pump, a third flow pump, a first servo valve, a second servo valve, a third servo valve and a fourth servo valve, wherein the first flow pump, the second flow pump and the third flow pump are respectively driven by a first motor, a second motor and a third motor. By applying the hydraulic system, the stepless speed regulation can be available within a certain scope, and the problem that a stepless speed regulation technology of a traditional hydropress is narrow in adaptive aspect is solved; according to different speeds, a different quantity of flow pumps are used; the direct return of large-flow high pressure liquid to an oil tank is avoided, so that the energy can be effectively saved; when one small flow pump and the servo valve connected with the small flow pump are adopted for synchronous regulation, the precision of synchronization between the first hydraulic cylinder and the second hydraulic cylinder is effectively improved, and the unbalance loading resistance capability of equipment is improved.