The common causes of hard inguinal lymph nodes include lymphadenitis, localized sebaceous glands, and lymph node tuberculosis. 1. Lymphadenitis: mostly caused by local injury, peripheral inflammation spread, infection, clinically, the main manifestation of inguinal lymph nodes red and swollen, accompanied by the symptoms of hardness and pressure pain. 2. Local sebaceous glands: the distribution of human hair follicles is very concentrated, if the sebaceous glands, resulting in poor drainage, and accompanied by bacterial infection. Then there will be the situation of hard lumps in the groin. 3. Lymph node tuberculosis: usually caused by tuberculosis mycobacterium infection, clinically mainly manifested as inguinal lymph nodes red, swollen, and hard texture. When patients appear inguinal lymph nodes have hard lumps, should be timely consultation, under the guidance of professional doctors, clear examination and treatment.