Cancer pain at night is because it is quieter in the dead of night, without peripheral environmental stimulation, and patients are more focused, accompanied by insomnia, when they feel increased pain, but cancer pain is persistent pain, and it also hurts during the day. During the day, there are various peripheral environmental influences that distract patients, and they will feel some pain relief. Clinical observation shows that cancer pain exists 24 hours a day, and some patients will have eruption pain no matter in daytime or at night, and the pain is so intense in eruption pain that the VAS score can generally reach 10, at which time intervention is needed. In addition, not all patients have eruptive pain at night, most of them have eruptive pain in the afternoon, so cancer pain does not necessarily occur all at night, but 24 hours a day, which requires 24-hour supervision of patients by medical staff.