Feeling hot in the legs may be caused by lower extremity venous thrombosis, multiple peripheral neuritis and other diseases. 1. Lower extremity venous thrombosis: the occurrence of this disease is related to venous blood flow stagnation, venous wall damage, blood hypercoagulability and other reasons, often triggered by age, smoking, obesity, pregnancy, surgical braking and other factors, resulting in patients with unilateral lower extremity swelling, pain, fever and other symptoms. 2. Multiple peripheral neuritis: the causes of this disease are commonly found in drugs, chemicals, nutritional disorders, alcoholism, infections and so on. Due to multiple peripheral neuritis, patients will have symptoms such as limb sensory disorder, autonomic nerve disorder, and symptoms such as pins and needles and burning sensation in the legs. If patients always feel feverish in the legs, they should go to the hospital in time to do relevant examinations to clarify the specific causes.