  We propose a novel leptogenesis mechanism wherein the coupling between the
right-handed neutrino and Standard Model particles is temperature-dependent. In
this mechanism, the coupling experiences suppression at high temperatures and
becomes sizable when the washout processes are Boltzmann-suppressed. This
temperature-dependent coupling ensures that the washout rates consistently
remain lower than the Hubble expansion rate, allowing all generated lepton
asymmetry to survive. We illustrate this mechanism through two toy model
examples and demonstrate that the observed baryon asymmetry of the Universe can
be successfully obtained for right-handed neutrino masses larger than
$10^9~{\rm GeV}$ as well as for smaller CP-violation values.
