Method for controlling a rail pressure (p7 Soll) caused by a high-pressure pump in a fuel accumulator for a fuel supply system of an internal combustion engine, wherein a crank angle-related or cam angle-related fixed angle difference of the internal combustion engine, between an upper dead-center position of a cylinder piston of a cylinder of the internal combustion engine and an upper dead-center position of the pump piston of the high-pressure pump of the fuel supply system, is taken into account in the metering of the delivery volume of the high-pressure pump, wherein for each segment, which corresponds to a revolution of a crankshaft and thus the movement of the pump piston of the high-pressure pump from the upper dead-center position of the pump piston to the next upper dead-center position, a discretization of a control deviation (Δp 7) of the rail pressure in the fuel accumulator is carried out repeatedly in a pump-synchronous manner, and a volume-related discrete volume control difference (ΔV Rail) is calculated from the discrete control deviation (Δp 7), wherein the discrete control deviation (Δp 7) is calculated as a difference from the discretized actual rail pressure (p7 Ist) and the discretized setpoint rail pressure (p7 Soll), characterized in that discretized pressure information (p7 Ist) of a rail pressure sensor of the actively detected pump-synchronous segment is compared with the discretized setpoint rail pressure (p7 Soll) of the pump-synchronous segment that precedes the actively detected segment by a working cycle in order to determine the discrete control deviation (Δp7), wherein the volume-related discrete volume control difference (ΔV Rail) is supplied as an input variable to a control module (C1n) for the high-pressure pump and a control module (C8n) for a pressure control valve assigned to the fuel accumulator, wherein the discrete volume control difference (ΔV Rail) is linked to a pilot control module, as a result of which the control variables for the high-pressure pump and the pressure control valve are calculated in an output module in a pump-synchronous manner for each segment and are supplied to the control elements (E1, E8) of the high-pressure pump and of the pressure control valve for volume-based adjustment of the rail pressure (p7 Soll). the discrete control deviation (Δp 7) is calculated as a difference from the discretized actual rail pressure (p7 Ist) and the discretized setpoint rail pressure (p7 Soll), characterized in that discretized pressure information (p7 Ist) of a rail pressure sensor of the actively detected pump-synchronous segment is compared with the discretized setpoint rail pressure (p7 Soll) of the pump-synchronous segment that precedes the actively detected segment by a working cycle in order to determine the discrete control deviation (Δp7), wherein the volume-related discrete volume control difference (ΔV Rail) is supplied as an input variable to a control module (C1n) for the high-pressure pump and a control module (C8n) for a pressure control valve assigned to the fuel accumulator, wherein the discrete volume control difference (ΔV Rail) is linked to a pilot control module, as a result of which the control variables for the high-pressure pump and the pressure control valve are calculated in an output module in a pump-synchronous manner for each segment and are supplied to the control elements (E1, E8) of the high-pressure pump and of the pressure control valve for volume-based adjustment of the rail pressure (p7 Soll).