This 54-year-old man diagnosed as esophageal cancer had suffered from insomnia and relied on the sleeping pills for a long time. After receiving chemotherapy and immunotherapy, insomnia exacerbated with less than 10 minutes sleep and thereby an episode of delirium occurred. Due to the impaired liver function and elevated ammonia in serum, the physician avoided the prescription of hypnotics and suggested him receiving the acupuncture intervention. After once acupuncture intervention, his sleep latency significantly reduced and the sleep duration prominently lengthened. Moreover, no more delirium was seen. In this case report, we demonstrated acupuncture could improve the sleep efficiency. Our report implies that acupuncture maybe be beneficial for improving insomnia and quality of life in cancer patients.