Abstract: Objective: Further evaluate the effect, safety of transdermal fentanyl (Durogesic) and the influence to the quality of life in patients with cancer pain in order to help the clinical use. Methods: Four hundred thirty-three patients with moderate or severe cancer pain were treated with transdermal fentanyl. The initial dose of transdermal fentanyl was 2.5mg or according to NCCN guides. Transdermal fentanyl was changed every 3 days. The dosage was adjusted by pain intensity in order to obtain pain free or mild pain. The period of observation was 45 days. Results: Cancer pain relief was 100% in 336 evaluated patients. Dosage adjustment was not needed in 41.6% patients after the initial use, in 57.3% patients adjusted 1 to 3 times. The median dosage of transdermal fentanyl is 7.5mg. The range of dosage was from 2.5mg to 7.5mg in 92.9% patients. The adverse reaction was mild. The main adverse events were nausea, constipation, dizziness, vomiting, dysuria. There was a significant improvement for quality of life in the patients after treatment. Conclusion: Transdermal fentanyl is an effective, convenient and safe medication for relief of moderate or severe cancer pain. It can improve the quality of life in the patients with cancer painA The adjusting times in the majority of the patients is within 3 times. The dosage of transdermal fentanyl in most patients is from 2.5mg to 10mg every 3 days.