Raynaud’s phenomenon refers to: when stimulated by cold or emotional and nervous, the skin of the finger appears pale and cyanotic, numbness, coldness and tingling at the end of the finger, the skin becomes flushed, then there is a sense of warmth and swelling, and then the skin color returns to normal, and the symptoms disappear. To put it simply, it is a process of finger skin from normal → pale → cyanotic → flushed → normal after being stimulated by cold and so on. What do we need to pay attention to when we find Raynaud’s phenomenon? Raynaud’s phenomenon is divided into two kinds: primary and secondary; the cause of primary Raynaud’s phenomenon is not clear, and may be related to cold stimulation, endocrine disorder and nerve excitation. Secondary Raynaud’s phenomenon refers to the appearance of Raynaud’s phenomenon on the basis of the original disease. In clinical work, secondary Raynaud’s phenomenon is common, and in the clinical work of rheumatology, Raynaud’s phenomenon is even more common. Raynaud’s phenomenon is common in many rheumatic immune diseases. Therefore, when patients develop Raynaud’s phenomenon, they need to be alert to the possibility of rheumatic immune diseases, such as vasculitis, scleroderma, dry syndrome, lupus erythematosus, myositis and dermatomyositis. Only when the primary disease is well controlled, Raynaud’s phenomenon can be relieved.