A mobile device for distinguishing a user's movement, a method therefor, and a method for generating a hierarchical tree model therefor. Particularly, the mobile device includes: an acceleration sensor; a buffer for collecting the acceleration data outputted from the acceleration sensor according to a user's specific movement; an extraction unit for extracting the characteristic elements of the user's specific movement based on the acceleration data collected by the buffer; and a movement judgment unit for determining to which class the user's specific movement belongs by inputting the characteristic elements extracted by the extraction unit into a pre-structured hierarchical tree model, wherein the hierarchical tree model is pre-structured based on the characteristic elements extracted for each movement.