Abstract: A method for simulating the operation of an internal combustion engine, using a single-cylinder test bench device, and a data-processing device executing an engine simulation model which simulates a multi-cylinder internal combustion engine. The engine simulation model determines a simulation value of at least one simulation variable, to be simulated, of the multi-cylinder internal combustion engine, in particular air mass flow and/or exhaust gas recirculation rate on the basis of at least one test bench. operating value, in particular indicated mean pressure and/or exhaust gas temperature, which is detected at a defined test bench operating point of the single-cylinder test bench device by means of a measuring device and fed to the data-processing device.