The cause of eye swelling should be analyzed case by case: if it is unilateral eye swelling, it may be eye allergy, mosquito bites or trauma; if it is bilateral eye swelling, it may be local or systemic factors, and the specific cause should be reasonably judged under the guidance of a doctor. 1. Unilateral eye swelling: It may be due to ophthalmologic lesions, such as conjunctivitis, or mosquito bites, eyelid allergies, some drugs or cosmetics may lead to unilateral eye swelling. 2. Bilateral eye swelling: caused by systemic diseases, such as nephrotic syndrome, heart failure, etc., there will also be eye swelling. If the swelling of the eyes persists and does not exist without relief, you should consult a doctor in time to clarify the specific cause and follow the doctor’s instructions for active treatment.