【Abstract】 Objective To explore the analgesic effect of different doses of oxycodone intravenous patient controlled analgesia (PCIA) and epidural patient controlled analgesia (PCEA) for patients after prostate surgery and provide an optimal choice for clinical treatment. Methods 210 patients who underwent prostatectomy in our hospital from January 2018 to January 2020 were randomly divided into 6 groups A1, A2, A3, B1, B2 and B3, with 35 cases in each group. PCIA scheme was used for postoperative analgesia in groups A1, A2 and A3. Oxycodone+tropisetron 10mg+0.9% sodium chloride solution of 0.6mg/kg, 0.8mg/kg and 1.0mg/kg were used to 100mL respectively. PCEA scheme was used for postoperative analgesia in groups B1, B2 and B3. Oxycodone+tropisetron 10mg+0.9% sodium chloride solution of 0.6mg/kg, 0.8mg/kg and 1.0mg/kg were used to 100ml respectively. The vital signs, visual pain analogue scale (VAS) and adverse reactions of 6 groups were compared before operation (T0), 6h (T1), 12h (T2), 24h (T3) and 48h (T4). Results There was no significant difference in the levels of map, HR and SPO  (2) at different time points in each group (P＞0.05). The VAS scores of group B1, B2 and B3 at T1, T2, T3 and T4 were significantly lower than those of group A1, A2 and A3 (all P＜0.05), the VAS scores of group A2 and A3 at T1, T2, T3 and T4 were significantly lower than those of group A1 (all P＜0.05), and the VAS scores of group B2 and B3 at T1, T2, T3 and T4 were significantly lower than those of group B1 (all P＜0.05). The incidence of adverse reactions in B1, B2 and B3 groups were significantly lower than those in A1, A2 and A3 groups (all P＜0.05). The incidence of adverse reactions in B1 and B2 was significantly lower than that in A2 and A3 groups (P＜0.05), and the incidence of adverse reactions in A3 group was significantly higher than that in A1 and A2. The incidence of adverse reactions in B3 group was significantly higher than that in B1 and B2 groups (all P＜0.05). Conclusion For prostate surgery patients, the analgesic effect and incidence of adverse reactions of different doses of oxycodone PCEA are significantly better than different doses of oxycodone PCIA, and when the dose of oxycodone is 0.8 mg/kg, Best effect.