Background Chronobiology indicates that many kinds of physiological proceedings such as blood pressure, heart rate, cardiac output, and immunological and inflammatory processes all exhibit a circadian pattern. Objective To explore the interaction of biological rhythm and anesthesia. Content Many research showed that biological rhythm can exert effect on sedation, hypnosis, analgesia, muscle relaxation and clinical anesthesia work, and inversely, anesthesia can divert or reset biological rhythm. Trend Further study was needed for the mechanism of interaction of biological rhythm and anesthesia.