Pain is a very frequent problem in patients with cancer, with a prevalence of 90% in advanced disease. The management of cancer pain is complex, and a multidimensional approach is necessary for its optimal treatment. Three types of pain have been described based on the neurophysiology of pain pathways (somatic, visceral and neuropathic pain). Numerous guidelines for the management of cancer pain have been issued by various organizations and researchers. The WHO guideline is the most used in the management of pain cancer. The opioids analgesics, of which morphine is the prototype, are the most important drugs in the treatment of cancer pain. Adjuvant drugs are used in the treatment of cancer pain, in order to enhance opioid analgesia, and provide analgesia for certain specific types of pain (neuropathic pain, and bone pain).