Objective To compare the knee of patient controlled subcutaneous injection of morphine analge-sia after hip joint replacement ( PCSA ) and intravenous morphine patient-controlled analgesia ( PCIA ) effect and safety of postoperative analgesia.Methods 60 patients undergoing artificial total knee arthroplasty patients were selected and randomly divided into PCIA group of 30 cases,30 cases in group PCSA, two patients were completed under epidural anesthesia in the operation.Group PCIA and group PCSA single dose divided into 1mg/and 2.5mg/, lock time divided into 5min,20min,in the postoperative pain perception,from the patient's own pain medication.After 4h,8h,12h,24h record patient morphine dosage,frequency,pain score (VAPS),mean arterial blood pressure and re-spiratory rate,compose degree,analgesic effects were compared between the two groups.Results In group PCSA after 24h treatment for the total dose was (30.41 ±10.00) mg,significantly higher than that of group PCIA (18.03 ± 6.04)mg,there was significant difference between the two groups (t=3.98,P<0.05);but after each time point of the two groups of patients the average dosage had no statistically significant difference (P>0.05).PCIA group after 0-4h and >4-8h analgesia and sedation were better than those in PCSA group (t=3.4,3.2,3.5,3.7,all P<0.05), PCIA group,the incidence rate of nausea and vomiting was 30%,higher than 12%in the PCSA group,there was sig-nificant difference between the two groups (χ2 =5.76,P<0.05).Conclusion The two kinds of methods of analge-sia has a good analgesic effect,but PCSA analgesia is slower,less adverse reactions,should be given a loading dose at the beginning before PCSA,in order to improve the early analgesia effect.