Abstract: The invention relates to a method for regulating a hydrostatic drive system which has at least one pump which is driven by an internal combustion engine and at least one hydraulic motor which is driven by the pump, and comprises the method steps: determining the volume flow rate flowing through the hydraulic motor; determining a first adjustment nominal value for the hydraulic motor as a function of the previously determined volume flow rate rate; determining a second adjustment nominal value by modifying the first adjustment nominal value by a correction value which is determined as a function of the nominal/actual value deviation of the internal combustion engine rotational speed by means of a vehicle-specific characteristic curve which incorporates the different power profiles for traction and overrun operation, respectively, of the internal combustion engine, with the hydraulic motor being adjusted in such a way that a substantially constant pressure level is generated at the maximum power level of the in