Abstract:objective To compare the analgesic effects and adverse reactions between sufentanil and morphine rapid titration treatment in advanced refractory cancer pain. Method Eighty cases of advanced cancer pain were treated with sufentanil, 68 patients were treated with morphine by rapid patient-controlled intravenous analgesia(PCIA) titration to control pain. Before titration, the dosage of opiate drugs was converted to intravenous sufentanil or morphine doses according to the equivalent dose relationship of opiates. 24 hours after titration, the sufentanil or morphine doses were converted to fentanyl patches. Pain scores and sleep quality were compared between the two groups before and after treatment. Adverse reactions were recorded from the beginning titration. Result There were no significant differences in pain scores, sleep quality scores between two groups after titration (P < 0.05), in addition, the pain and sleep quality scores were significantly lower. Results comparing to morphine group, sufentanil group had a lower incidence of adverse reactions. Conclusion Both sufentanil and morphine injection showed good analgesic effect in the rapid titration treatment of cancer pain. Compared with morphine injection, sufentanil had a lower incidence of adverse reactions.