Light shelf applications are one of the improved daylight system, help to contribute energy saving by using daylight effective. Latitude is an important parameter that affects the placement and efficiency of light shelf. The placement and efficiency of light shelf on 30 degrees & 45 degrees latitudes that includes Turkey is investigated for a typical Office unit with different office heights in this study. Ecotect and Radiance software is used in calculations. Consequently, it is determined that the usage of interior positioned light shelf is suitable and the efficiency of light shelf increases with office height within determined conditions on 30 degrees and 45 degrees latitudes.