As Result from many environment issues all around the world, renewable power generation methods are in the spotlight. A solar tower is one of these methods of renewable power generation using thermal updraft air flow caused by solar energy. The purpose of this study is to improve a power generation performance of the solar tower system, and baffles are selected as a means of increasing power generation on the solar tower. Several simulations are carried out on the size, number and spacing of the baffles inside the solar tower using commercial code, ANSYS Fluent 17.0. Through this simulation, we confirmed the possibility of improving the performance of the solar tower.