A method for editing the playback speed of a partial sequence of video and a digital device therefor are disclosed. A video editing method includes providing a timeline interface corresponding to a video sequence, receiving a first user input for specifying a first location on the timeline interface and a second user input for specifying a second location on the timeline interface, setting an editing interval between the first location and the second location of the timeline interface, receiving a third user input with respect to the editing interval, adjusting at least one of the thickness and length of the editing interval in response to the third user input, and editing playback attributes of the partial sequence based on the adjusted thickness and length of the editing interval.