The invention relates to the technical field of demineralizers of power plant boron recycling systems and provides a CPR1000 nuclear power plant boron recycling system reducing dosage rate. The system includes a coolant collecting pipeline, a front storage water box, a demineralizer, a degasser, an intermediate storage water box, a boron water separator, a water storage box, a boric acid storage box, a recycling pipeline, a bypass pipeline, a bypass valve and a demineralizer valve. When a nuclear power plant is in a working condition of coolant degassing treatment, the demineralizer valve is closed and the bypass valve is opened so as to enable the coolant to flow through the bypass pipeline and then into the degasser. Therefore, absorption of LiOH by the demineralizer when the coolant flows through the demineralizer is avoided, consumption of the LiOH is reduced, PH value balance of the coolant is ensured, corrosion product settlement in a cooling loop is reduced, dosage rate during an overhaul period is reduced and the cost is reduced.