Gene gun administration of DNA is an invaluable technique for transfecting tissues with only 1 μg DNA/shot. Here, we describe a transfection technique of healthy corneas of BALB/c mice with a standard gene gun, using a technique that can avoid tissue destruction even when high pressure is used (e.g., 700 psi). The focal transfection of the cornea to improve corneal disease may be an advantage over other transfection methods in order to avoid unwanted bystander transfection in other compartments of the eye or body.