A method of controlling an activation area of a touch screen panel and an electronic device using the same. A method of operating an electronic device, according to an embodiment of the present disclosure, may include: setting a partial area of a touch screen panel, which corresponds to a view window of a cover that is mounted on the electronic device, as an effective touch area when the cover is closed; and when the cover mounted on the electronic device is closed, activating the partial area of the touch screen panel that corresponds to the set effective touch area. In addition, the various embodiments of the present disclosure also include other embodiments as well as the above-described embodiment.