The hardening and cracking of the skin on both sides of the nails may be caused by physiological factors such as lack of water in the skin, or it may be caused by diseases such as ringworm, palmoplantar pustulosis, etc. It is recommended that the patient take general treatment, medication, and physical therapy to improve the situation. 1. Physiological factors: If the skin is dry or dehydrated, it may cause the skin on both sides of the nail to become hard and cracked. Daily need to eat more fresh fruits and vegetables, ensure adequate water intake, and use petroleum jelly and other moisturizing products to moisturize the skin. 2. Ringworm: Ringworm may cause the skin on both sides of the nails to become hard and cracked, patients need to apply moisturizing products to moisturize the skin, such as petroleum jelly. Patients should apply antifungal drugs such as clotrimazole and sertaconazole as prescribed by the doctor to promote the recovery of skin lesions. For patients with hyperkeratosis, medications such as salicylic acid should be applied to help exfoliate the skin. 3. Palmoplantar pustulosis: palmoplantar pustulosis may trigger the skin on both sides of the nails to be hard and cracked, the patient can follow the doctor’s instructions to apply halometasone, dexamethasone and other glucocorticoid ointment to reduce inflammation and relieve itching. Oral vitamin A drugs such as Avitamin A may also be prescribed to relieve skin symptoms. In addition, photochemotherapy such as narrow-spectrum medium-wave ultraviolet light and complementin combined with ultraviolet A band can be used. The causes of hardening and cracking of the skin on both sides of the nails are relatively numerous, and after excluding physiological factors, patients are advised to consult a doctor for examination to clarify the cause of the disease and cooperate with the doctor for standardized treatment.