Swollen eyes in the morning may be caused by drinking too much water before going to bed, allergies, conjunctivitis and other reasons. 1. Drinking too much water before going to bed: If you drink too much water before going to bed, and the water can not be discharged in time after drinking too much water, it may gather in the eyelid area, resulting in the appearance of swollen eyes in the morning. 2. Allergy: Before going to bed at night, if the eyes are in contact with skin care products, dust mites and other allergens, it is easy to cause an allergic reaction, which may lead to the phenomenon of swelling of the eyes in the morning, and may be accompanied by eye itching, eye pain and other symptoms. 3. Conjunctivitis: If you suffer from conjunctivitis, due to the presence of inflammation in the eye, under the stimulating effect of inflammation, can lead to swelling of the eyes in the morning, can also be accompanied by redness, tearing and other symptoms. The eyes may also be swollen in the morning due to kidney disease and other organ diseases, in the exclusion of non-physiological causes, you should go to the regular hospital in time to identify the cause of the disease, under the guidance of a professional doctor to take targeted treatment.