  The new mechanism for the generation of the chiral generations is proposed
based on the SU(1,1) horizontal gauge symmetry. The appearance of the chiral
generations is controlled by the coupling constant s of the model. This is
crucial in the grand unification scheme. The resulting chiral generations
naturally acquire the hierarchal Yukawa coupli ng matrices. Propriety of the
model to the observed hierarchical structure is discussed nume rically under
the minimal parameter set.
