The paper shows the possibility of using the fallen leaves of poplar for cultivating mushrooms of the genus Trichodermа. It is established that the litter is available as a substrate for growth of filamentous fungi. In the process of microbiological conversion is possible to type the drug "Trichodermin" and humic substances. Using the fallen leaves of the poplar as raw materials for bioconversion allows to solve the problem of disposal of vegetable wastes.