Redness and pain on both sides of the butt crack may be related to contact dermatitis, perianal eczema, perianal abscess and so on. 1. Contact dermatitis: it may be due to wearing underwear of poor quality or too tight, causing local skin allergies, redness and pain on both sides of the butt crack. 2. Perianal eczema: it may be due to allergy, mental stress, local friction and other reasons. Resulting in the anal opening and its surrounding skin, pimples, blisters and so on. However, there are also cases of redness and pain involving the buttocks. 3. Perianal abscess: pathogens such as Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa. Caused by the rectum, the soft tissues around the anal canal appear to be infected with pus, etc., can also appear in the area of the buttock fissure to appear redness, pain. When there is redness and pain on both sides of the gluteal fissure, it is recommended to consult a doctor in time, follow the doctor’s instructions for further examination, clarify the cause with the help of the doctor, and carry out targeted treatment or therapy.