Children waking up with swollen eyes may be caused by drinking too much water, poor sleep, conjunctivitis and other reasons. 1. Drinking too much water: If children drink too much water before bedtime, it will increase the burden on the kidneys, and poor metabolism will occur, which will easily lead to waking up with swollen eyes. 2. Poor sleep: if children do not rest well at night, or sleep too late, as well as sleep in the head position is low, resulting in poor blood circulation around the eyes, water will be retained in the eye area, there will be waking up swollen eyes. 3. Conjunctivitis: caused by microbial infections, external stimuli and allergic reactions, which can lead to redness of the eyes, photophobia, excessive secretions, and swelling of the eyes after waking up. There may be other reasons for children’s eyes to be swollen after waking up from sleep, so it is recommended that the patient consult a doctor in time to clarify the specific cause and carry out appropriate treatment if necessary.