Abstract: This disclosure describes a machine for treating organic waste, comprising a casing which defines an inner treatment chamber for organic waste delimited at least in part by a screening grid, and an inlet opening for waste at one end of the chamber and an outlet opening at an end opposite to the inlet opening; at least one driven shaft installed in the inner chamber and provided with mechanical means for grinding or pressing the introduced organic waste against the screening grid or against at least one wall which delimits the inner treatment chamber; a first motor, having a drive shaft functionally coupled to the driven shaft; a first transmission system configured to transmit to the driven shaft a rotational movement imparted by the first motor to the drive shaft, the first transmission system comprising at least one first support bearing functionally coupled to the drive shaft.