The causes of painful skin on the inner thighs are considered to be caused by both genital herpes and ringworm, specifically into the following: 1. Genital herpes: considered to be genital herpes, mainly in the groin of the thigh, as well as the scrotum, mons pubis, labia appearing as erythema, papules, clusters of blisters, unilaterally distributed, and accompanied by pain, which is an infectious skin disease caused by the varicella-zoster virus. The skin is a contagious skin disease caused by the varicella zoster virus. Therefore, for treatment, you can take oral ganciclovir dispersible tablets and adenosine cobalamin tablets, and for topical medication, if the blisters are ruptured, you can use topical stove glycolic lotion, and if the blisters are ruptured, you can mix comfrey oil and spray ciclovir cream for topical use. 2. Tinea corporis: Tinea corporis is considered to be a fungal skin disease, which is mainly due to the appearance of erythema and papules at the root of the thighs after friction from wearing tighter underwear for a long time. It is also covered with a thin layer of scales, accompanied by itching, and after a long period of friction, it causes redness and pain in the skin inside the thigh root. It is advisable to wear cotton, loose underwear, and also to mix topical application of bifenazole cream and tretinoin econazole cream. If the itching is severe, you can also take oral Orotadine Hydrochloride tablets and Terbinafine Hydrochloride tablets at the same time. Therefore, for painful inner thigh skin, patients are advised to go to a regular hospital and undergo appropriate laboratory tests under the guidance of a dermatologist to guide the clinical treatment.