Ruptured capillaries in the leg can usually heal spontaneously if they occur due to external forces, but if they are spontaneously ruptured, they may be caused by their own blood diseases, such as coagulation disorders, idiopathic thrombocytopenic purpura, etc., which are generally more difficult to heal spontaneously. Capillaries are located at the distal end of the arteries and veins, the diameter of the blood vessels is thin, if trauma occurs, it is easy to rupture, after the rupture of the capillaries, petechiae or small hematoma will appear, and can be absorbed by themselves after 1~2 weeks. Patients can apply cold compresses within 24 hours of capillary rupture and hot compresses after 24 hours to promote the absorption of petechiae and hematomas. If petechiae appear on the legs for no reason, we should be alert to spontaneous capillary rupture, which may be a blood disorder. For example, idiopathic thrombocytopenic purpura can be seen as bleeding spots under the skin, or as bruises and purpura. Coagulation disorders such as vitamin K deficiency can lead to cutaneous petechiae, ecchymoses, which are usually less severe. This condition is more difficult to heal on its own and requires prompt treatment in a hospital. Patients who experience leg capillary rupture should go to the hospital promptly to identify the cause of the disease and actively treat it, after excluding the factor of external force.