Abstract: The study gives considerations over application of polypropylene fiber for fiber reinforcement of fine-grain concretes. There was performed experimental analysis of fiber-concrete samples produced with use of a composite binding agent. There was established a percentage of fine-grain concrete fiber reinforcement with polypropylene fiber which was equivalent to 4 kg/cub.m. This value can be explained by the fact that the further increase of fiber reinforcement ratio results in insignificant enhancement of service properties of concrete and in some cases even in impairment of the same due to reduction of concrete layer thickness to the extent when the material tends to segregation.