Provided are an electronic device and an operating method thereof. The electronic device includes a display, a plurality of optical sensor units arranged to respectively correspond to a plurality of regions divided on the display, a memory storing one or more instructions, and a processor configured to execute the one or more instructions stored in the memory, in which the processor is further configured to, by executing the one or more instructions, determine an intensity and a direction of external light incident to each of the plurality of regions divided on the display, by using the plurality of optical sensor units, determine a shadow region on the display, based on the determined intensity and direction of the external light corresponding to each of the plurality of regions, and control the display to provide a shadow effect on the determined shadow region, overlappingly with an image that is currently displayed on the display.