Sebaceous cysts are a common benign lesion on the face, limbs, and back, and are often symptomatic. Sebaceous cysts are mostly found on the face, limbs and back, and are a common benign lesion with no obvious symptoms. The main danger of facial acne is that it affects aesthetics. If accompanied by infection, it can induce redness, swelling, pain, tenderness and other symptoms. If the infection is not treated in time, the cyst will rupture and form a scar, and it is easy to recur. Sebaceous cysts on the limbs and back may not only become infected, but may also gradually increase in size, causing pressure on the surrounding tissues. A small number of sebaceous cysts may become cancerous, mainly basal cell carcinoma, and in a few cases, squamous cell carcinoma, but the rate of cancer is low, around 2%. Patients with sebaceous cysts should be monitored carefully. If infection occurs, they should consult doctor in time and follow the doctor’s instruction to be treated accordingly; if it affects aesthetics or pressure or cancer, they should have it removed by surgery in time, and do pathological examination if necessary.