In this study the main elements of a hydrostatic regenerative braking system have been modeled. The model which has been created the elements in the system and the relationship of the system with the vehicle has been studied. In order to measure the performance of the regenerative system driving cycles for moving and stopping the vehicle using only the hydraulic system have been simulated. Simulation studies have indicated that by using this system a vehicle such as a heavy truck can be acceleated to the first speed range and the energy needed for it can again be stored by the regenerative braking system. In determining the elements of the improved model that can be used in experimental studies the calculation of losses is also planned by taking into consideration these issues.