An electronic device includes a main body including at least one display, a wearable part connected to at least a part of the main body, a detector that detects information of a fastening position of the wearable part, and at least one processor that performs a function corresponding to the fastening position detected by the detector. A method for operating an electronic device including a wearable part connected to at least a part of the a main body includes detecting information of a fastening position of the wearable part, and performing a function corresponding to the detected fastening position. Various other embodiments are disclosed.