  The U(1) flavor symmetry explains the large mixing of neutrinos while it
leads to the unique texture for the quark mass matrices. It is remarked that
U(1) symmetric mass matrices have the phenomenological defects. In the quark
sector, the mixing $V_{ub}$ is predicted to be large compared with the expected
value $\l^4$ at the GUT scale. In the lepton sector, U(1) charges, which give a
large mixing in the neutrino sector, also lead to the large one in the charged
lepton sector. In the viewpoint of the flavor symmetry, this is an unpleasant
feature because the neutrino mass hierarchy is determined only by unknown
coefficients of ${\cal O}(1)$, and the near-maximal flavor mixing is not
guaranteed in the case of both large angle rotations. These defects disappear
by introducing additional discrete symmetries $Z_2\times Z_2'$. The $U(1)\times
Z_2\times Z_2'$ quark-lepton mass matrices are presented by taking account of
the recent data of atmospheric neutrinos and solar neutrinos.
