A magnetic-inductive flow meter with at least one measurement tube, a magnetic field generating apparatus for generating a magnetic field which runs at least also perpendicular to the longitudinal axis of the measurement tube, and two measurement electrodes, the measurement tube having a metallic base body provided with a thermoplastic cover layer, a virtual connecting line of the two measurement electrodes running perpendicular to the direction of the magnetic field which is permeating the measurement tube perpendicular to the longitudinal axis of the measurement tube. The penetration sites of the measurement tube at which the measurement electrodes penetrate the measurement tube are easily made liquid-tight by a liquid-tight connection which has been produced by heating of the cover layer at the penetration sites for sealing the thermoplastic cover layer of the measurement tube to the measurement electrodes.