Patients presenting with unilateral eye swelling and pain may be related to visual fatigue, eye trauma, blepharitis, etc. Visual fatigue is a persistent spasmodic ciliary muscle disease caused by prolonged close work or viewing of electronic products. Patients may experience eye swelling and pain, as well as dryness, soreness and other uncomfortable symptoms. Ocular trauma is categorized into mechanical and non-mechanical, of which mechanical ocular trauma includes non-perforating trauma and perforating ocular trauma. Eye trauma can cause significant pain, swelling of the eye, bruising of the skin, and other uncomfortable symptoms. Blepharitis refers to purulent inflammation of the eyelid glands. Under the stimulation of inflammation, patients may experience discomfort such as eyelid swelling and pain, accompanied by burning sensation in the eyes, photophobia and tearing. It is recommended that patients with obvious swelling and pain in the eyes should consult a doctor in time to assess their condition and follow the doctor’s instructions for treatment. Patients should also pay attention to rest, avoid overuse of the eyes, and maintain eye hygiene.