The invention discloses an operation method of a pressure control system. The pressure control system comprises a pump, a first switch, a second switch, a first three-way valve, an energy accumulator,an hydraulic cylinder, a second three-way valve, an oil tank, a solenoid valve, a gate valve, and a control device; the operation method comprises a driving method, a pressure relief method, a pressure reduction and energy storage method, and an energy storage feedback method, the energy storage feedback method comprises the following parts: the downstream end of the energy accumulator is connected to the second three-way valve; the three ends of the second three-way valve are respectively connected with the main circuit, the energy accumulator and the oil tank; the main circuit comprises a branch circuit of the energy accumulator, and the branch circuit parallel of the second switch; a second pressure sensor is arranged in the energy accumulator; a pressure signal of the second pressuresensor is fed back to the control device; when the control device judges that the energy accumulator needs to release the energy for feedback, the control device controls the energy accumulator to start, and controls the second three-way valve to connect with the energy accumulator and the first cavity.