In a method for forming the mixture in a combustion space of an internal combustion engine, fuel is injected into the combustion space with a varying fuel mass flow during an operational cycle of the internal combustion engine. In one embodiment at least under certain engine operating conditions, three-stage fuel injection is carried out during the compression phase so that a main fuel quantity is injected in a first injection step, an additional fuel quantity with a reduced fuel mass flow is injected in a second injection step and an ignition fuel quantity is injected in a third injection step. In another embodiment, a fuel quantity is injected with a fuel mass flow which is reduced so that it falls steadily from a maximum initial value down to zero and, in accordance with a third method, a fuel quantity is injected during the induction phase with a fuel mass flow which is, at least at times, proportional to the air mass flow.