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Centralized hydraulic systems such as load-sensing electro-hydraulic control (LS) systems realize flow distribution through multiple valves, resulting in large throttling losses and low energy efficiency. The distributed independent electro-hydraulic control system (DIEHCS) adopted the displacement control mode of single pump and single actuator, which basically eliminated throttling loss and had remarkable energy-saving effect, but there were many problems such as large installed power of independent drive and uncompact distributed installation structure. Therefore, a distributed independent secondary-pressure-regulation electro-hydraulic control system (DIEHCS-SPR) was proposed for a 6 t excavator. The system consisted of three open electro-hydraulic actuators (EHAs) which independently arranged on the manipulator and a constant pressure main pump (arranged in the cabin). Each EHA achieved four-quadrant operation according to the expected actuator speed and load direction. The simulation results of 6 t excavator virtual prototype show that proposed DIEHCS-SPR was compared with LS system, the energy saving rate was up to 42%~46% under the same working cycle. Compared with the existing DIEHCS, the proposed system can reduce the peak output power of each EHA by up to 70%~74%, resulting in a significant reduction in individual EHA dimensions and weight, while saving key component (EHA) manufacturing costs and additional energy consumption from self-weight during distributed installation.