Abstract：This paper summarizes Professor HUANG Yan's views on the physiological characteristics of the brain，one of the extraordinary fu-organs，and mainly expounds on the relationship between brain and blood. Professor HUANG believes that， ① the brain governs the mental activity and is based on blood. People's mental activities are dominated by the brain， and mental changes are closely related to the five viscera. The physical base of communication between the brain and the five viscera in mental activities is blood. ②The brain governs the five viscera to manage blood. The brain regulates the function of the five viscera to ensure the orderly operation of blood in the body. ③The brain contains the blood to transform the vital activity. The brain absorbs the nutrient and blood supplied by the viscera and bowels to transform and generate the vital activity in the extraordinary fu-organs. The vital activity dominates such physiological functions of the human body as movement and perception. ④ The original spirit is the courier， and the nutrient and blood are the guard. The original spirit outside is the embodiment of the physiological function of the brain， and the blood inside is the physical basis of the brain. The brain and blood are closely related， interdependent，and fundamental to each other in mutual generation，promotion，and fostering.