  We report on an on-going two-flavor full QCD study on CP-PACS using an
RG-improved gauge action and a tadpole-improved SW quark action. Runs are made
for three lattice spacings $a^{-1}\approx 0.9$, 1.3, and 2.5 GeV on
$12^3\times24$, $16^3\times32$, and $24^3\times48$ lattices. Four sea quark
masses having $m_{\rm PS}/m_{\rm V} \approx 0.8$--0.6 are simulated, for each
of which hadron masses are evaluated for valence quark masses corresponding to
$m_{\rm PS}/m_{\rm V} \approx 0.8$--0.5. Results for hadron and light quark
masses are presented and compared with those obtained in quenched QCD.
