Provided are an electronic device and operation method thereof. The electronic device may include: a display having a biometric sensing region; a biometric sensor disposed in the biometric sensing region; and a processor. The processor may be configured to: operate a first sub-region of the biometric sensing region according to a first display attribute and operate a second sub-region of the biometric sensing region according to a second display attribute; while the first sub-region is operated according to the first display attribute and the second sub-region is operated according to the second display attribute, obtain, through the biometric sensor, a signal corresponding to an external object, wherein the signal is generated at least partially based on light that is emitted from the first sub-region or the second sub-region and reflected by the external object; perform authentication on the external object if the signal satisfies a specified condition; and prevent authentication on the external object if the signal does not satisfy the specified condition.