Abstract: Objective : To observe analgesic effect and main side effects of Oxycontin in management of the moderate and severe cancer pain. Methods : Oxycontin was administered at an initial dose of 10mg every 12 h and titrated upwards according to the extent of pain relief. Evaluated outcomes included analgesic effect, Karnofsky Performance Status Scales (KPAS) and side effect. Results : The mean time for onset of analgesic effect was 41 minutes and mean duration of analgesic effect was 12.6h. The daily mean dose was 69.03mg. Among all the 31 patients suffering moderate and severe cancer pain, one (3.23%) achieved slightly pain relief. The moderate, obvious and complete pain relief occurred in 4 (12.90%), 20 (64.52%) and 6 (19.53%) patients, respectively. KPAS was elevated in 19 patients(61.29%)and stable in 9(29.03%)after application of Oxycontin. Three patients (9.68%) died of deterioration. Main adverse effect was constipation in 10 patients (32.26%). Conclusion : Oxycontin works quickly, safely and effectively and has comparatively slight adverse effects in treatment of the moderate and sever cancer pain.