Cancer pain is one of the most common symptoms in cancer patients, which seriously affects the quality of life of cancer patients. The incidence of pain in patients with primary diagnosis of cancer is about 25%; the incidence of pain in patients with advanced cancer is about 60%-80%, and 1/3 of them have severe pain. If cancer pain (hereinafter referred to as cancer pain) is not relieved, patients will feel extremely uncomfortable, which may cause or aggravate patients’ symptoms such as anxiety, depression, fatigue, insomnia, loss of appetite, etc., which seriously affects patients’ daily activities, self-care ability, socialization ability, and the overall quality of life, and further affects the timely radiotherapy and thus affects the survival time, therefore, chronic cancer pain has been regarded as an independent disease by the World Health Organization (WHO). Therefore, chronic cancer pain has been regarded as an independent disease by the World Health Organization (WHO) and requires timely treatment. At present, under the leadership of the Ministry of Health, the oncology departments of various hospitals are carrying out the construction of “Cancer Pain Standardized Treatment Demonstration Ward” with great fanfare, which is a declaration of war against cancer pain. Zhu Qiyong, Department of Oncology, Guilin No. 5 People’s Hospital Since cancer pain is a kind of disease that seriously affects the quality and duration of survival of cancer patients, timely treatment is needed. The first step is to carry out cancer pain assessment, which is a prerequisite for rational and effective pain relief treatment, including routine assessment and quantitative assessment. Cancer pain assessment should follow the principles of “routine, quantitative, comprehensive and dynamic” assessment. Routine assessment of cancer pain refers to the healthcare personnel taking the initiative to ask cancer patients whether they have pain, routinely assess the pain condition and make corresponding medical records, which should be completed within 8 hours after the patients are admitted to the hospital. For cancer patients with pain symptoms, pain assessment should be included in the routine monitoring and recording of nursing care. Routine assessment of pain should identify the causes of explosive episodes of pain, such as pain due to pathologic fractures requiring special management, brain metastases, infections, and emergencies such as bowel obstruction. There are three methods for quantitative assessment of cancer pain, namely, the numerical rating scale (NRS), the facial expression assessment scale, and the complaint pain rating scale (VRS). The Numerical Rating System (NRS) is commonly used in clinical practice: the degree of pain is represented by 0-10 numbers in sequence, with 0 indicating no pain and 10 indicating the most severe pain. The patient chooses the number that best represents his or her pain level, or the healthcare provider asks the patient: how severe is your pain? , this question is up to the patient, and the doctor records how much pain the patient says they have. The pain level is categorized according to the number corresponding to the pain: mild pain (1-3), moderate pain (4-6), and severe pain (7-10). The objectives of cancer pain treatment are to eliminate pain continuously and effectively, control cancer pain to completely pain-free or mild pain; limit the adverse effects of drugs; minimize the psychological burden caused by pain and treatment; and maximize the quality of life. Statistically, after regular analgesic drug treatment, more than 95% of patients’ cancer pain can be effectively controlled. Mild pain (1-3): general treatment or implied treatment is enough, commonly used drugs include aspirin enteric-coated tablets and Daifen capsules, etc., but they should not be applied continuously for a long period of time in order not to cause serious complications such as gastric perforation. Medium and severe pain (4-10): opioids are preferred. At present, short-acting opioids commonly used in the treatment of cancer pain are morphine immediate-release tablets, and long-acting opioids are morphine extended-release tablets, oxycodone extended-release tablets, and fentanyl transdermal patches. The specific usage and dosage of opioids should be determined by oncologists in a scientific way to avoid potential complications. When applying opioid painkillers for a long period of time, the preferred route of administration is oral, but of course there are also anal plug applications, vaginal plugs, etc. that cannot be administered orally. When there is a clear indication, the transdermal absorption route can be used to administer the drug, or temporary subcutaneous injection of the drug, if necessary, can be self-controlled analgesic drug delivery. When it comes to the application of opioids, it is necessary to talk about the problem of invisibility. This problem we do not need to worry too much, because after the evidence-based medicine, as long as the standardized application of opioids, regardless of the application of how long, how much dose, 1,000 users have not become a real addict. On the contrary, some of its adverse reactions need to be taken seriously. If a single opioid is not effective in relieving pain, an adjuvant drug can be added, which can enhance the pain-relieving effect of opioids or produce a direct analgesic effect. Adjuvant analgesics are commonly used to assist in the treatment of neuropathic pain, bone pain, and visceral pain. The choice of type of adjuvant medication and dosage adjustment needs to be individualized. Of course, there are other therapeutic means, such as interventional therapy, including nerve block, nerve release, percutaneous vertebroplasty, nerve destructive surgery, nerve stimulation and radiofrequency ablation. There are also treatments such as radiation therapy, cause-specific chemotherapy, and so on.