Patients lose half of their eyelashes, the causes of which mainly include blepharitis, ocular seborrheic dermatitis, mite parasites, trauma and so on. 1. Blepharitis: Blepharitis is mainly caused by chronic bacterial infection of the eyelid or eyelash root, because the inflammation will affect the hair follicles at the root of the eyelashes, so it will lead to eyelash loss. Usually, eyelash loss caused by ulcerative blepharitis cannot be regenerated, while eyelash loss caused by scaly blepharitis can be regenerated. 2. Ocular seborrheic dermatitis: usually caused by bacterial infection or stress, if not treated in time, it can damage the hair follicles and make the eyelashes fall off, so we suggest that the patients pay attention to eye cleaning. 3. Mite parasitism: Mites can easily parasitize the eyelash roots and block the opening of the blepharoplasty glands, affecting the function of the blepharoplasty glands and causing eyelash loss. 4. Trauma: Eyelid trauma or eyelid burns can cause scarring of the eyelid, leading to eyelash loss and implantation of eyelashes. 5. Other: If the patient has been using poor quality cosmetics or other chemicals for a long time, it can cause irritation to the eyelash follicles, which can also cause relaxation of the follicles and lead to eyelash loss. It is recommended that patients with severe eyelash loss and other uncomfortable symptoms seek medical attention in a timely manner to assess their condition and follow the doctor’s instructions for treatment.