  For the purpose of deriving the observed nearly tribimaximal neutrino mixing,
a possible quark mass matrix model is investigated based on a yukawaon model.
The neutrino mass matrix is related to the up-quark mass matrix. Five
observable quantities (2 up-quark mass ratios and 3 neutrino mixing parameters)
are excellently fitted by two parameters (one parameter in the up-quark mass
matrix and another one in the neutrino mass matrix). Also, the CKM mixing
parameters and down-quark mass ratios are given under the other 2 parameters.
