  We study the thermal leptogenesis in a hybrid model, which combines the so
called split fermion model and the bulk neutrino model defined in five
dimensional spacetime. This model predicts the existence of a heavy neutrino
pair nearly degenerate in mass, whose decays might generate a CP violation
large enough for creating the baryon asymmetry of the universe through
leptogenesis. We investigate numerically the constraints this sets on the
parameters of the model such as the size of the compactified fifth dimension.
