The objective was to observe the clin. effect of oxycodone hydrochloride injection and fentanyl on Stretch reaction in appendectomy under epidural block and the security.The method includes selecting 60 patients who will receive appendectomy, randomly dividing them into observation group and control group with 30 patients into each group, performing appendectomy after epidural block effect is definite, i.v. injection of oxycodone hydrochloride 0.1 mg/kg+Tropisetron Mesylate 6 mg and then pump injection of oxycodone 2μg/(kg·min) until the abdomen was closed, i.v. injection of fentanyl 1μg/kg+Tropisetron Mesylate 6 mg and then pump injection oxycodone 2μg/(kg·min) until the abdomen was closed, monitoring SBP, DBP, HR, ECG and SpO2 change before the appendectomy, at skin incision, incision of abdominal cavity, Stretch appendix and the end of appendectomy, and assessment of the internal organs stretch reaction state.The results show that oxycodone hydrochloride injection has good therapeutic effect, little untoward effect and big assurance coefficient for preventing Stretch reaction in appendectomy under epidural block.