A method is provided for measuring the mean flow velocity of an electrically conductive medium while applying a magnetic field to the measurement volume put through and decoupling an electric signal induced in the measurement volume. The fluctuating part of the electric signal, which is based on stochastic fluctuations of the flow velocity due to turbulent motion, is captured as a time-dependent wanted signal. By the weighted integration of the wanted signal the mean flow velocity over predefined time intervals is determined.