Analysis of tests on soils with randomly distributed fibre reinforcement an possibilities of its application in geotechnical and environmental engineering were presented in the paper. Using this type of reinforcement make it is possible to form flexible earth structures with green surfaces and relatively high resistance on different settlement substituting heavy, rigid and strange in the landscape concrete structures. By mixing synthetic fibers, both specially produced as reinforcement or other ones eg. recovered from waste carpets or foils, with soil and sometimes very small amount of cement, shear strength resistance and its residual value increase is achieved. Reinforcement dose not disturb growth of plants or water infiltration, so the fiber-soil composite is an environmental friendly solution. Higher strength is positively influencing other soil parameters like piping resistance or resistance against erosion, but in this field of application there is much less investigation data.