The present invention discloses a mobile terminal capable of controlling a size of a video in accordance with a size of a file attachable to a message and a method of controlling therefor. The mobile terminal includes a display unit configured to display information, a wireless communication unit configured to perform wireless communication, a memory configured to store a video and a controller, if a size of the video is bigger than a limit size of an attachable file supported by a messaging service usable for transmitting the video, configured to generate a plurality of slice files from the video in accordance with the limit size, the controller configured to control one of a plurality of the slice files to be attached to a message.