Inflammation and hyperplasia of the groin can be caused by localized infections or lesions around the lower limbs, perineum and groin. 1. Lower limbs: inflammation of lower limbs, such as cellulitis of lower limbs, lower limb trauma complicating infection, abscess, dengue, foot fungus complicating infection will cause inflammation of inguinal lymph nodes. When malignant tumors appear in the skin of the lower limbs, inguinal lymph node metastasis can occur, causing inguinal lymph node inflammation, hyperplasia and so on. 2. Perineum: infections in perineum, such as vestibular gland abscess, cervicitis, epididymitis, perirectal inflammation, perianal abscess, etc. can cause inguinal lymphadenitis. Penile cancer, testicular cancer, female vulvar cancer can cause inguinal lymph node hyperplasia and inguinal inflammation. 3. Peri-inguinal: Inflammation and infection around the groin, bacteria enter into the groin and cause localized inflammation and hyperplasia in the groin. Inflammation and hyperplasia in the groin require timely consultation and various examinations under the guidance of a doctor to find out the cause of the disease and give appropriate treatment.