Ｏｂｊｅｃｔｉｖｅ　To compare the analgesic effect of continuous adductor canal block(ACB) and continuous femoral nerve block(FNB) after total knee arthroplasty(TKA).　Methods　Sixty patients scheduled for unilateral TKA were randomly assigned into two groups, receiving continuous ACB(group A) or continuous FNB(group F). Intravenous anesthesia was applied throughout the operation. The adductor canal and the femoral nerve were catheterized for block under the guidance of sonography before induction of general anesthesia. Patient-controlled analgesia was provided immediately after surgery with 0.2% ropivacaine through the perineural catheter. The pain severity at rest and upon movement (passive knee flexion of 45 degrees) with a 0－10 numeric rating scale (NRS), the Lovett score of muscle strength of the quadriceps femoris, and the modified Bromage score of the motor block of the affected extremity were assessed 4, 8, 12, 24, 48 h after surgery. The maximal range of active/passive motion of the knee joint was recorded 1, 2, 3, 14 d after surgery. The number of effective patient-controlled bolus of ropivacaine and the number of need for opioid rescue within 48 h after surgery, the first time of out-of-bed activity, the time of active knee flexion reaching 90 degrees, and the hospital for special surgery(HSS) score of knee function 14 d after surgery were also recorded.　Results　There was no difference between group A and group F in terms of the NRS scores at rest and upon movement, the number of effective patient-controlled bolus of ropivacaine and the number of need for opioid rescue (P>0.05). Patients in group A had a higher Lovett score of muscle strength of the quadriceps femoris and a lower modified Bromage score of the motor block than those in group F within 12 h after surgery (P<0.05). The maximal range of active motion of the knee joint 1, 2, 3 d after surgery was larger in group A than that in group F(P<0.05). No significantdifference was observed between two groups regarding the maximal range of passive motion of the knee joint, the maximal range of active motion of the knee joint and the HSS score of knee function 14 d after surgery, the first time of out-of-bed activity and the time of active knee flexion of 90 degree(P>0.05).　Conclusions　An equal postoperative analgesic efficacy was observed in patients receiving continuous ACB and continuous FNB. Furthermore, continuous ACB did not provide a superior effect on early rehabilitation than continuous FNB.