An electronic device includes a housing including a cover glass and a back cover facing the cover glass, a display disposed inside the housing and including a plurality of pixels disposed in the display, a first printed circuit board interposed between the display and the back cover, a second printed circuit board interposed between the first printed circuit board and the back cover, a fingerprint sensor disposed on the first printed circuit board and configured to obtain fingerprint information of a user based on light reflected from a finger of the user making contact with the cover glass, and a processor disposed on the second printed circuit board and adjusting brightness of first-group pixels disposed at an area corresponding to the fingerprint sensor. The processor increases the brightness of the first-group pixels to be proportional to time in which the user makes contact with the cover glass with the finger.