The invention relates to a method for operating a drive train of a motor vehicle, wherein the drive train comprises a drive motor and an automatic or automated transmission connected between the drive motor and the drive wheels, wherein the transmission automatically changes gear in an automatic mode, wherein the transmission changes to a higher or lower gear in a manual mode on the basis of an up-shift or a down-shift requested by the driver by means of a control element, and wherein, at least in automatic mode, a coasting mode of the drive train, in which the operative connection between drive motor and drive wheels is separated, is engaged under defined operating conditions and the coasting mode is disengaged upon the driver requesting a down-shift and the manual mode of the transmission is engaged. According to the invention, the coasting mode is maintained in automatic mode in the case of the driver requesting an up-shift during coasting mode.