Heparin is the commonly anticoagulant used in Continuous Renal Replacement Therapy (CRRT). Thrombosis could reduce the efficacy of CRRT. Patients with hypertension who undertake CRRT increase the risk of thrombosis. The current study was to explore the proper concentration of heparin for patients with hypertension during CRRT. In our study, 225 patients without hypertension were control subjects (A group) and 225 patients with hypertension were enrolled (B group). According to Activated Partial Thromboplastin Time (APTT) before CRRT, the patients of A and B groups were divided into low risk-hemorrhage population (APTT<55 s) and high risk- hemorrhage population (APTT ≥ 55 s), respectively. After CRRT, the patients in low risk-hemorrhage population from A and B groups were subjected to 1000 IU/ml and 500 IU/ml heparin saline, respectively; while patients in high risk-hemorrhage population from A and B groups were given 500 IU/ml and 250 IU/ml, respectively. The double-lumen of dialysis catheters was used to carry out blood purification treatment and monitor the coagulation parameters including APTT, Prothrombin Time (PT) and International Normalized Ratio (INR). It was showed that 250 IU/ml of heparin was an appropriate concentration for sealing tube in all patients with APTT ≥ 55 s; 500 IU/ml heparin was an appropriate concentration for sealing tube in patients with hypertension (APTT<55 s).