Whether or not 300 diopters of myopia can be achieved without glasses depends on the age of the myopic patient as well as the visual acuity without glasses. In small children, 300 diopters of myopia will affect their vision, usually with a visual acuity of 0.1 or even lower, which will affect their studies and aggravate the increase of myopia. Therefore, it is recommended and necessary to wear glasses in children, and need to be reviewed regularly every six months. If the myopia grows too fast, it may be necessary to replace the glasses in time, or wear keratoplasty lenses to control it. If in adults, especially the usual work using computer or cell phone crowd, close work 300 degrees is not affect the vision, usually can not wear glasses. However, for people working at a distance, such as drivers or crane workers, who need to see objects at a distance, 300 degrees will affect their eyesight, so they need to wear eyeglasses for this kind of occupations, but for people working at a distance, it is possible to wear eyeglasses with or without glasses.