Controller of the high pressure fuel pump position rod drive is the inner loop of the diesel crankshaft rotation frequency control. To make a high fast of the loop of regulating of the diesel crankshaft rotation frequency the inner loop is to be faster. Under such conditions there is a necessity to take into account the discreteness of the work of the voltage converter of the actuator.In the report the questions of design of the fuel pump rod position control are considered on the basis of the method of state-space in the discrete domain. Design includes receiving of the linear difference equations describing of the open loop with the impulse width modulation. The main feature of the description offered in the report is in the direct using the system of the differential equations to get the linear system of the linear difference equations without the step of making up the analytical solution of the differential equations. For this purpose the expressions in the common view have been received.On the basis of the received system of the linear difference equations the analysis and synthesis of the fuel pump rod position control loop are fulfilled. Two cases of the synthesis are considered. The results of the synthesis have been checked on the mathematical model of the fuel pump rod position control system. This model takes into account non linearity connected with the impulse width modulation. The received results show that the method of the synthesis of the feedback systems control with the impulse width modulation by using the linear difference equations is suitable for practical aims.