In this paper, a low-high pressure double oil hydraulic system with accumulators was presented with the features of high working efficiency, high control precision and large working capacity. To analyze the hydraulic system energy characteristic, a novel analytical approach, based on the mathematical energy dissipation model of hydraulic components, was proposed to calculate the system energy dissipation by establishing high accuracy simulation model. A test rig with a 10,000 kN hydraulic fine blanking press was built up and used to validate the proposed system and the energy analytical approach. Finally, the system energy dissipation of the 10,000 kN hydraulic fine blanking press was analyzed and the pump output pressure was optimized to minimize the energy dissipation with the genetic algorithm. Results indicate that the energy efficiency of the hydraulic fine blanking press hydraulic system is low, and especially under low-load conditions it is (0-50% full load rate) less than 15%. About 50% of the total input energy is consumed in the form of valve dissipation resulted from the imbalance of installed and demanded energy. After optimization, the total input energy decreases by nearly 50% and the energy efficiency increases by 10%, especially under low-load conditions.