Considering the hazards of noise pollutions and their increasing trend, nowadays, sound insulations are of the utmost importance. Some available insulating blankets in the market are made of foam and absorb moisture, while the other types of common insulations are fragile and vulnerable. Most of the insulations cannot be used in available construction materials and decrease the beauty of atmosphere. The insulations, which do not have the mentioned problems, are expensive. The current study aims at introducing an insulation, which does not have these problems and resists moisture at a reasonable price. This insulation is made of natural rubber and polyester fibers. It has a considerable flexibility and can be combined with other construction materials. In this experimental study, different samples of one-layer and two-layer natural rubbers with 2.2 mm thickness for each layer were produced with and without fibers in compression molding method. They were tested in various frequencies and compared with the results of common XPS sound insulation. Each of the samples had a good performance in a specific frequency. All samples exhibited an acceptable behavior compared with their peers in the market. Each of the samples performed better at a certain frequency. In conclusion, the best performance is related to the two-layer rubber sample with fibers and the present insulation in the market is in the second rank.