Swollen right eye may be caused by trauma, allergy, eye inflammation and other reasons. 1. Trauma: When the right eye is impacted, rubbed by foreign objects, etc., blood accumulation and edema may appear, which is manifested as swelling of the right eye. 2. Allergy: animal hair, pollen, cosmetics, etc. may cause allergic symptoms, resulting in edema of the right eye, which may also be accompanied by itching, rash and other symptoms. 3. Ocular inflammation: such as blepharitis, conjunctivitis, keratitis and other diseases, the eyes are stimulated by inflammation, can appear unilateral eyelid redness and swelling, conjunctival edema and other symptoms, can also be accompanied by increased eye secretions and other manifestations. It is recommended that patients go to the hospital in time to clarify the cause of the disease and follow the doctor’s instructions for treatment.