Disclosed are a method and a system that could adaptively improve the visual quality of people with low-vision impairment, regardless of network and terminal. The low-vision impairment is described by a set of "symptoms" that is semantically defined. As the description tool of low vision impairments, it is flexible and reliable to use the proposed "symptoms" based descriptions rather than individually identified names of eye disease, because the user can describe his/her low-vision impairment by specifying associated symptoms based on his/her own experience. The inputted visual contents are adaptively transformed according to the low vision-impairment.