Objective: To evaluate the analgesic effect of pregabalin combined with intrathecal sufentanil infusion for the treatment of breakthrough pain in patients with bone metastases. Methods: A total of 60 breakthrough pain patients with bone metastases were randomly divided to 3 groups: group A (pregabalin combined with intrathecal sufentanil infusion group,n=20), group B (placebo combined with intrathecal sufentanil infusion group,n=20) and group C (oral morphine sulfate controlled-release tablet group,n=20). The differences in visual analogue scale (VAS)between background pain and breakthrough pain, the seizure frequency of breakthrough pain, general satisfaction and side effects of the 3 groups were observed. Results: hTe seizure frequency and VAS of breakthrough pain in group A decreased signiifcantly after the treatment (P<0.05) and the general satisfaction was the best among the the 3 groups (P<0.05), with less nausea and vomiting, constipation, drowsiness and fewer other side effects. Conclusion: Pregabalin combined with intrathecal sufentanil infusion can effectively relieve breakthrough pain in patients with bone metastases.