Abstract: With a high incidence, cancer pain is an unresolved clinical problem right now. Many randomized controlled studies have shown that intrathecal infusion of analgesic drugs is an effective way to relieve pain. Intrathecal drug infusion system provides clinicians with exact individualized treatment approach in the effective analgesia, but with minimum side effects. Patients who received intrathecal analgesic therapy in the early stage would get more benefit. Before implanting intrathecal drug delivery devices, it is needed to test analgesic effect firstly, and the proper implementation of the test period is extremely important. This effectively maintaining time decides whether the patients need intrathecal analgesia system. However, there are many factors that may affect its application in clinic. This article focuses on the treatment principle, patient selection, testing, technical problems and complications when applying intrathecal drug delivery devices.