  We investigate the production of fourth generation neutrino in the context of
new $e \nu_4 W$ magnetic dipole moment type interaction in $ep$ collisions at
the future lepton-hadron colliders. We have obtained the mass limits of 700 GeV
for THERA ($\sqrt S$=1 TeV) and 2.8 TeV for LC$\otimes$ LHC ($\sqrt S$=3.74
TeV).
