Rosacea, commonly known as “red nose”, looks a bit like a clown in a circus, and most patients have no obvious discomfort, but it affects the aesthetics. The disease is mostly seen in middle-aged people, especially women, the onset of the disease is slow, at first manifested as the nose paroxysmal temporary red class, sometimes occurring and disappearing, in the consumption of certain irritating food, blowing cold wind, sun or emotional changes easily triggered or aggravated, over time, the red spot is persistent, the tip of the nose, nose and cheeks can appear “red blood” ( capillary dilation). After a few years, on top of the erythema, small red bumps and pustules appear, often one after another, and the erythema becomes more obvious. After a few years or a dozen years, the sebaceous glands at the end of the nose become hyperplastic and the tip of the nose and nose become enlarged, forming nodular or tumor-like protrusions, unevenness, enlarged pores, and more coarse red blood. This kind of severe rosacea is mainly seen in advanced male patients. The cause of rosacea is not fully understood and is related to physical and genetic characteristics. It may be due to certain internal and external environmental factors that trigger vasomotor nerve dysregulation in the face and prolonged capillary dilation. It does not matter whether the skin is oily or not. Trichophyton infection is one of the factors in the development of rosacea, but not the only one. Alcoholism, spicy food, high temperature, sun exposure, cold, mental factors, gastrointestinal dysfunction, endocrine disorders, and the presence of infected lesions are all contributing and aggravating factors. The prevention of rosacea is more important than the treatment. Those whose nose is prone to redness should avoid the above triggering and aggravating factors related to themselves, so that rosacea can be controlled at the initial mild stage, and if it has developed to the stage of papules, pustules or even nasal redundancy, it is still necessary to avoid the relevant triggering factors to avoid further aggravation. Drugs containing hormones can dilate facial capillaries. They should be avoided. In recent years, the use of dye pulse laser treatment of capillary dilation has achieved significant results, and after the capillary dilation disappears, the nasal redundancy will also be reduced. In short, patients should be aware of this disease, strengthen prevention and early treatment.