Abstract: Objective To evaluate the analgesic effect of different dose of oxycodone during post-anesthesia recovery in the patients undergoing functional endoscopic sinus surgery (FESS). Methods Total 90 patients planned to receive FESS, aged 18-60 years, weighing 55-85 kg, ASA status I or Ⅱ, were randomized and assigned into group A, group B and group C (n=30).The patients in group A, B and C received oxycodone of 0.1, 0.15, 0.2 mg/kg, respectively.Oxycodone was given at 30 min before the termination of FESS.HR, SBP, DBP and SPO₂ were recorded at the surgery closure (T₁), extubation (T₂), 10 min after extubation (T₃) and departure from PACU (T₄);Time to spontaneous breathing and extubation, SAS during extubation, Ramsay and VAS 20 min after extubation termination, satisfaction score of extubation, and the cases of nausea and vomiting were also recorded. Results The cases of nausea (12 cases) and vomiting (12 cases) in group C were the most among the three groups (P < 0.05);HR, SBP and DBP were significantly different among the three groups at T₂ (P < 0.05);HR, SBP and DBP at T₃ in group A, and HR, SBP and DBP at T₄ were the highest in the three groups;SPO₂ at T₃ in group C was the lowest (P < 0.05);The SAS was significant differences among the three groups (P < 0.05);In group A, extubation satisfaction score and VAS were the highest, while the Ramsay was the lowest among the three groups (P < 0.05). Conclusion The 0.15 mg/kg of Oxycodone is the ideal dose for post-anesthesia recovery of patients undergoing functional endoscopic sinus surgery.