Ｏｂｊｅｃｔｉｖｅ　To study the relative factors which influence the post-anesthesia care unit (PACU) stay of the patients underwent the lower limb orthopedic surgery.　Methods　A total of 442 patients who underwent orthopedic surgery from 2014 to 2017 were investigated. According to the patients′ anesthesia and recovery records, the age, sex, hemoglobin(Hb), surgical procedures, bleeding volume and anesthetic methods, etc. were collected. The possible variables that lead to the discharge delay from PACU were assigned for the regression analysis. The Logistic regression analysis was used in the analysis of the related factors of the delay in PACU.　Results　The age, anemia, pulmonary function, kidney function, American Society of Anesthesiologists(ASA) level, use of dexmedetomidine (Dex), the consumption of fentanyl, inhalation anesthetics, lumbar-sciatic nerve block, urine volume, hypothermia, bleeding volume, infusion volume and transfusion volume had effects on the delay in PACU. Multivariate analysis showed that the age>65 years, Hb<100 g/L, forced expiratory volume in one second (FEV1)<60%, high ASA grade and hypothermia can prolong the duration of PACU stay after operation. The use of Dex, lumbar-sciatic plexus block, urine volume can shorten the time in PACU.　Conclusions　Age, Hb level, lung function, ASA level, the use of Dex, lumbar-sciatic plexus block, urine volume, body temperature and transfusion volume were related to the duration in PACU in patients with orthopedic trauma surgery.