The present invention relates to a method for providing image data based on cloud streaming. The method uses memory space of a terminal to minimise the network load required for transmitting video data, stores image data in the terminal in advance, captures an execution screen regarding the execution of a particular application, extracts relevant video content from pre-stored image data based on the captured execution screen and the information regarding the execution screen, simultaneously encodes the extracted plurality of video contents and provides the same on a screen. By using resources of the terminal, the usage of a cloud streaming server and network can be reduced, the network load can be reduced if live videos or VOD videos are not watched, and a rich GUI can be guaranteed in a stand-by mode. By exposing movie previews, soap opera trailers and advertisements in the stand-by mode, the purchase of chargeable videos is encouraged and thus sales can be increased, and personalised services can be strengthened with short news or personalised videos.