This article deals with the comparison of the energy consumption of the hydraulic control system of the working mechanisms of the telescopic excavator UDS 114. There is described the hydraulic system of the excavator. In order to compare the individual losses in the hydraulic circuits for controlling the working mechanisms, the hydraulic oil flow rates through the OTC H50 meter were measured. Firstly, for the machine before a repair and subsequently after the repair. For each hydraulic circuit, the hydraulic oil flow rates between the pump and the distributor and then between the distributor and the appliance were measured at first. The overall power losses of the hydraulic circuit is then determined from particular calculations. From these calculated power losses of individual hydraulic circuits, the efficiency of individual hydraulic circuits in the state of the machine before and after repair was evaluated.