Objective To explore the feasibility and effect of infusion pump potassium supplementation in continuous renal replacement therapy (CRRT). Methods Patients who underwent CRRT were randomly divided into infusion pump group and traditional way group between March and May 2018. In infusion pump group, 10% potassium chloride was supplemented with infusion pump. In traditional way group, 10% potassium chloride was supplemented in the traditional way, which meant adding potassium in the replacement solution. The peripheral blood potassium level, the potassium well-controlled rate, the incidence of adverse events, the average frequency of replacement liquid bags change, the average pump stopping time, and the delivery dose and potassium supplement dose between the two groups were compared. Results A total of 60 patients were randomly divided into two groups, with 30 cases in each group. The infusion pump group was treated with an average of 6.90 mL/h potassium supplement dose by infusion pump, and in traditional way group, potassium was added to the replacement solution by an average of 9.29 mL/h; there were significant differences between the two groups (P<0.05). When compared with traditional way group, there was no significant differences (P>0.05) in the peripheral blood potassium level and the potassium well-controlled rate of the patients at 0, 2, 8, 12 and 24 hours after CRRT (P>0.05). As for the adverse events rate, average frequency of replacement liquid bags change, average pump stopping time, and potassium supplement dose, there were significant differences between the two groups (P<0.05). Conclusions The application of infusion pump to supply potassium in CRRT is feasible and safe, and is superior to the traditional potassium supplement method. It could be further applied in clinical practice.