In a method for controlling a fuel injection system (10) of an internal combustion engine, wherein the fuel injection system (10) comprises a manifold (24) and a high-pressure pump (20) and a fuel dosing unit (16) is associated with the high-pressure pump (20), wherein the fuel dosing unit (16) controls the amount of fuel delivered, an amount of fuel required for the operation of the internal combustion engine is determined as a function of a correction factor, which is based on a fuel pressure at the inlet of the high-pressure pump (20) and/or on a vapor pressure of the fuel to be delivered.