Abstract: Data have shown that nearly 80% of patients with malignant tumors in China fail to receive effective control of cancer pain. Opioids, the classic analgesics, are commonly used in clinical practice for analgesia; however, they cause numerous adverse reactions. These adverse reactions during analgesic therapy can affect the patient's mood, social life, or daily activities to varying degrees, which consequently affect the continued use of analgesics. This consensus focuses on patients with cancer pain who are prescribed opioids for analgesia by healthcare providers and aims to suggest measures for the prevention and treatment of adverse reactions occurring during the opioid treatment.