Polyurethane (PU) foams are versatile in various applications due to their easiness of cost effectiveness and production process. The flexible polyurethane foam production cost is reliant on the price of polyol that comprise the major proportion of substances employed in foam synthesis and induce higher physical and mechanical characteristics. Hence, suitable fillers that are compara tively inexpensive can be added in the foam matrix as substitute for polyol has been studied. In this study, Polyurethane (PU) foams by introducing CaCO3 fillers were prepared to observe the density, tensile strength and elongation properties. Response surface methodology using Central composite design (CCD) has been employed to optimize these parameters. The optimization of CaCO3, Filler size, and Time parameters in order to study the effect on density, tensile strength and elongation were studied. The optimal values of were density of 24.799 Kg/m 3 , tensile strength of 125.169 KPa, and elongation of 113% at the optimum values of 20.010% CaCO 3 concentration, 23.179 µm filler size and 81 seconds. Hence, it is vital to employ various filler size, Time and CaCO3 concentration to attain and improve the physical and mechanical properties of the polyurethane composite foams. Key words: Polyurethane foam, CaCO3 filler, elongation, tensile strength density