A method of operating a drive train of a motor vehicle which includes at least an electric machine, as a drive aggregate, and a transmission which is positioned between the drive aggregate and an output, and a starting element positioned between the electric machine and the transmission. For and during the start, an expected drive resistance is calculated and then, if the expected drive resistance is lower than a first threshold value, starting takes place with the starting element engaged via the electric machine from a standstill, and if the expected drive resistance is larger than the first threshold value, starting takes place with the starting element disengaged, the electric machine is operated with a defined machine rotational speed in a rotation speed control mode, and thereafter, the starting element is engaged such that it transfers starting torque which depends on the a driver request.