  I report the status of the dynamical overlap fermion project by the JLQCD and
TWQCD collaborations. So far, the simulations have been completed with two
flavors of overlap sea quarks in a wide range of sea quark mass corresponding
the $p$-regime and the $\epsilon$-regime on a $16^3\times 32$ lattice at
$a=$0.12 fm. More recently, runs with 2+1 flavors of sea quarks have also
started. This talk mainly discusses the physics results on the $N_f=2$ lattice
after describing the lattice formulation and algorithms.
