The causes of eyelid redness, swelling, and pain are many, and may be related to blepharitis, trauma, and blepharosphenoid cysts. 1. Blepharitis: Blepharitis is mainly caused by staphylococcus and other bacterial infections, resulting in acute suppurative inflammation of the eyelid glands, which can cause redness, swelling and pain in the eyelids, and can be accompanied by conjunctival congestion and increased secretion in the eyes. 2. Trauma: If the patient’s eyelid is scratched by a tree branch or other reasons, local wound inflammation can cause redness, swelling, pain and other symptoms. 3. Blepharophalangeal cysts: Blepharophalangeal cysts can occur when the outlet of the blepharophalangeal gland is blocked, resulting in irritation of the surrounding tissues due to the retention of secretions, and if secondary infections occur, the patient may experience redness, swelling, and pain in the eyelids. It is recommended that patients with red, swollen and painful eyelids seek prompt medical attention to evaluate their condition and follow doctor’s instructions for treatment.