Pain caused by cancer is usually directly or indirectly caused by the tumor, or may be caused by cancer treatment. Patients can take corresponding analgesics to relieve pain under the guidance of professional doctors, generally available analgesics mainly include non-steroidal drugs, opioids, central analgesics, etc.: 1. They are suitable for cancer patients with mild pain; 2. Opioids: mainly include weak opioids and strong opioids. Common weak opioids include tramadol, dextropropoxyphene, oxycodone, codeine, etc. Strong opioids include morphine, remifentanil, sufentanil, allylmorphine, etc. These drugs have strong analgesic effect. These drugs have strong analgesic effect and are more suitable for cancer patients with moderate to severe pain, and have no toxic effect on organs under normal circumstances. 3. Central analgesics: Common central analgesics include carbamazepine, gabapentin and pregabalin, which are mainly used to relieve neuropathic pain. Patients need to follow the doctor’s advice and take the medication on time, in the right amount and according to the course of treatment, so as to avoid adverse reactions caused by overdose or forming a certain mental dependence on opioid analgesics. In addition, while taking analgesic drugs, it is recommended that patients actively cooperate with professional doctors for surgery, radiotherapy and other treatments according to the specific type and degree of cancer, which can help improve the cure rate, prolong the survival period and improve the quality of life of patients.