Provided is a network flow-based scalable video coding (SVC) adaptation device. Without permitting a network transmitting end to divide image data into image data having various levels of quality and send the image data having the various levels of quality to all networks, since an adaptation device is installed in a network device of an ingress of a lower network of a subscriber and the adaptation device and the network transmitting end share network information about attributes of a terminal and the lower network of the subscriber so as to provide an image service having image quality corresponding to the terminal to the terminal, network efficiency can be maximized.