In this paper, the mechanical and physical properties of thermoplastic polymer modified asphalt concrete mixtures were investigated. Three different thermoplastic polymer modifiers include; Ethylene vinyl acetate (EVA), Polypropylene (PP) and polyethylene terephthalate (PET) were studied. Constant polymer content of 3% by weight of asphalt cement was used in the studied mixtures. The Physical properties were evaluated in terms of softening point, penetration, kinematic viscosity and ductility tests, while the mechanical properties were evaluated based on Marshall stiffness, indirect tensile strength and unconfined compressive strength. Experimental testing has revealed the enhancement in the physical and mechanical properties of asphalt concrete mixtures when the three studied thermoplastic polymers were added. The EVA modified asphalt had the lowest penetration and highest softening point, kinematic viscosity and ductility. The EVA modified mixture also has experienced the highest Marshall stiffness, fracture energy, indirect tensile strength and unconfined compressive strength. Measurements of the heat dissipation rate of the studied polymer modified mixtures revealed their ability to hold heat longer than conventional mixtures. PP and EVA modified mixtures displayed the lowest rate of heat dissipation.