Abstract: Objective To evaluate the safety and efficacy of transdermal fentanyl（duragesic） dosage titrated by fentanyl patientcontrolled intravenous analgesia（PCIA） in patients with cancer pain. Methods From December 2011 to August 2013， 26 patients with moderate to severe cancer pain were studied. Titration conditions， pain score（NRS）， scores of pain impacting on life and adverse reactions were assessed and recorded respectively in the four period of treatment（before fentanylPCIA， the period of fentanylPCIA, duragesic with fentanylPCIA and the period of duragesic）. Results There were 21 cases of successful titration and 5 cases failed. The general pain score， the most serious pain score， activity pain score， resting pain score and scores of pain impacting on life were significantly reduced in the period of fentanyl-PCIA， the period of duragesic with fentanylPCIA and the period of duragesic compared with those before fentanyl-PCIA（P＜0.05）. The main adverse reactions occurred in the treatment were nausea and vomiting and no obvious muscle rigidity， loss of consciousness， cough， itching， respiratory depression and bradycardia were observed. Conclusion Titration of transdermal fentanyl with fentanyl administrated by PCIA is not only safe， effective and convenient， but also relieving breakthrough pain quickly， be worthy of clinical promotion.