Children with red blood spots under the skin may be related to allergic purpura, thrombocytopenic purpura, abrasions and other causes. 1. Anaphylactic purpura: contact with pollen and other allergens can cause dysfunction of the autoimmune system, which can lead to capillary rupture and the appearance of subcutaneous red blood spots. 2. Thrombocytopenic purpura: due to the low number of platelets or reduced function, which can lead to the appearance of subcutaneous bleeding spots. 3. Abrasion: The child’s skin is abraded, which can cause capillary rupture and lead to red blood spots under the skin. It is recommended that parents take their children to the hospital in time to clarify the cause of the disease and standardize the treatment under the guidance of the doctor, so as not to delay the disease to bring adverse effects on the body.