Swelling and pain under the eyes may be caused by trauma, blepharitis, orbital cellulitis, etc. as follows: 1. Trauma: When the eye is traumatized or contused, the local inflammatory reaction occurs, which can lead to pain, swelling and hematoma of the eye bags. 2. Blepharitis: commonly known as granuloma, is an inflammation of the eyelid glands of the eye by Staphylococcus aureus infection. If the bags under the eyes are red, swollen and painful, and there is a feeling of distension when pressed, it is considered as blepharitis. 3. Orbital cellulitis: generally due to sinusitis, trauma and other causes of inflammation of the soft tissues of the orbit. Orbital cellulitis is considered when there is redness, swelling and pain in the bags under the eyes, accompanied by conjunctival congestion and limitation of eye movement. When the symptoms of swollen and painful bags under the eyes appear, it is recommended to go to the ophthalmology department for examination, to clarify the specific cause of the disease, and standardize the treatment under the guidance of the doctor.