An image processing apparatus including: image processor which processes broadcasting signal, to display image based on processed broadcasting signal; communication unit which is connected to a server; a voice input unit which receives a user's speech; a voice processor which processes a performance of a preset corresponding operation according to a voice command corresponding to the speech; and a controller which processes the voice command corresponding to the speech through one of the voice processor and the server if the speech is input through the voice input unit. If the voice command includes a keyword relating to a call sign of a broadcasting channel, the controller controls one of the voice processor and the server to select a recommended call sign corresponding to the keyword according to a predetermined selection condition, and performs a corresponding operation under the voice command with respect to the broadcasting channel of the recommended call sign.