A foreign body on the corneal surface or embedded in the cornea is called a corneal foreign body. The common causes of corneal foreign bodies are: mud, sand, dust, etc. blown into the eye by high winds from farming or construction sites; small fragments splashed from tools, materials or surrounding objects into the eye when knocking, cutting or polishing metal objects or renovating; explosion injuries, car accident injuries, etc. can also cause corneal foreign bodies. Foreign bodies that enter the eye can be single, multiple or even diffuse. The effect on the eye depends on the chemical nature of the foreign body, its location, and the presence of infection. For example, inactive foreign bodies (e.g., plastic, sand) cause less damage to the eye than active foreign bodies (e.g., copper, iron); foreign bodies in the central cornea have a greater impact on vision than peripheral foreign bodies; the less clean the foreign body is the greater the chance of causing keratitis; and the greater the number of obligations the greater the impact on the eye. The common clinical symptoms of corneal foreign body include: obvious foreign body sensation in the eye, pain, eye redness, tearing, photophobia, blurred vision, etc. Improper treatment of corneal foreign bodies can cause corneal inflammation and corneal ulcers, leading to vision loss. Therefore, once a corneal foreign body is diagnosed, it should be removed as soon as possible; after the foreign body is removed, medication should be administered as prescribed by the doctor. Note: The removal of corneal foreign bodies should be strictly aseptic, and it is recommended to go to the hospital to find a professional to deal with corneal foreign bodies, not to handle them at home with needles or cotton swabs.