A method for operating a drivetrain of a motor vehicle including a hybrid drive with a combustion engine and an electric motor. A transmission is arranged between the hybrid drive and a drive output and a clutch is arranged between the combustion engine and the electric motor so that, if a failure occurs in the drivetrain, especially in a transmission control device of the transmission, a gear corresponding to an emergency gear is engaged or remains engaged in the transmission. When the emergency gear is engaged, the motor vehicle is in motion and the engine speed falls below a defined value, the clutch arranged between the combustion engine and the electric motor disengages.