Blood spots on the hands may be related to allergic purpura, senile purpura, thrombocytopenia and so on. 1. Allergic purpura: It may be caused by hemolytic streptococcus, influenza virus, fish and shrimp, etc., which leads to metamorphic reactions in the body. It causes immune complexes to be deposited in the blood vessel wall, activates the complement, causes inflammation in the capillary and small vessel wall, and may be manifested by blood spots such as bruises and petechiae on the hands. 2. Elderly purpura: due to the increased fragility of blood vessels in the skin and subcutaneous tissues of the elderly, minor trauma may also cause blood vessel rupture, resulting in blood spots on the hands. 3. Thrombocytopenia: If there are patients with thrombocytopenia, the skin and mucous membranes will bleed extensively after the hands are injured by impact. Platelets cannot help the body to stop bleeding at this time, and blood spots of different sizes may appear. Blood spots on the hands can also be seen in other causes, it is recommended to consult a doctor in a timely manner, follow the doctor’s instructions to carry out relevant examinations, with the help of the doctor to clarify the causes, and targeted treatment or treatment.