Method and electronic device for tracking eye

An electronic device is provided. The electronic device includes a light source module, a display module including at least one layer, a camera module, and a processor operatively connected to the light source module, the display module, and the camera module. The processor may emit light through the light source module along a waveguide formed in the at least one layer of the display module, may use the camera module to detect, based on at least one pattern structure formed in the waveguide, at least a part of the light, which has been reflected from a user's eyeball, and may track the movement of the user's eyeball, based on the detected light.