Noise, caused by the society and technical progress, is nowadays considered a pollutant. Noise pollution affects or could affect a great number of people. One the most concerned fields, in part by a growing law framework and by the quality expectations of the clients, is architecture. The solution to sound pollution involves eliminating it or reducing it to acceptable levels. Nowadays, one of the most recurred solutions is the use of lightweight materials such as gypsum boards, to create acoustic insulation elements. On the other hand, the environmental awareness has increased the attention towards recycled materials. In the case of composite materials, major attention has been devoted to the substitution of mineral reinforcements, such as glass fibers, by more sustainable reinforcements, as wood fibers or agroforestry wastes. In this sense, olive stones, which are a byproduct of olive oil extraction, could be used. In the present work, olive stone filled polypropylene composites were prepared. Different percentages of filler were used. The soundproofing properties of the composites were tested by means of an impedance tube. Then, the results were compared with those for gypsum boards, wood veneer and wood fiber reinforced polypropylene