Highways are very important in mobility and accessibility from and to any place. The growing traffic loads
causes many problems in the asphalt pavements. Researchers focuses on the applications of different additives in the field of asphalt paving. This paper is a literature survey that discuss the modification of asphalt. Additives may be added to the asphalt binder or to the aggregates. There are many different additives used in the modification of asphalt mixtures. Many of them have significant effects on the behavior of the asphalt binders or on the asphalt mixtures. Polymer is one of the most common additives used in asphalt modification. There are two types of polymers. The two types are thermoplastic polymers, and thermosetting polymers. Both types have great effects on the asphalt binder behavior. The main goal of using additives is to reduce the maintenance of the roads, improve the quality and durability. Reducing maintenance means reducing costs.