Asphalt concrete is used in the surface layer of road paving and is widely used around the world. Asphalt concrete consists of coarse aggregate , fine aggregate, filler and asphalt binder. Fly ash FA is one of the main wastes of coal-fired thermal and coal-fired power plants and is available in large quantities and has no use. The aim of this study is to evaluate the possibility of using fly ash as a filler material in hot asphalt mixtures and to use it as an alternative to natural fillers by performing laboratory work in which the asphalt mixture is designed and the optimal ratio of asphalt is determined . Then replace the filler material with 0, 25, 50, 75 and 100% with fly ash . The results showed that Marshall's stability values increased with increased replacement ratio and observed that Marshall's hardness values were decreased while remaining within the tolerable limits of the specifications. The study concluded that fly ash can be used as a filler in asphalt mixtures.