Cancer pain is the most common accompanying symptom of tumor, and it can be mild or severe. Most patients and family members have misconceptions about cancer pain, thinking that pain can be tolerated or not, and painkillers can be taken or not. The main concern is dependence, or they think that if they take them now, there is nothing they can do later. In fact, pain is an invisible harm to human body, and the consequences and harm caused are sometimes no less than the tumor itself. Therefore, nowadays, the clinical treatment of cancer pain should take priority over the treatment of tumor itself, and emphasize to let patients live pain-free. If the level of pain has affected your mood, your activities or your sleep, this situation must be controlled with pain medication. There are various grades and dosage forms of pain control medications, and your doctor will choose the right one for you according to the situation. Besides, cancer pain is not just “pain”, but also soreness, swelling, stuffiness, irritability and discomfort, which can be relieved by analgesic drugs.