  The latest results for open charm and $J/\psi$ production in p-p, d-Au and
Au-Au from the PHENIX and STAR experiments at $\sqrt{s_{NN}}=200$ GeV at RHIC
are presented. The preliminary data show open charm production follows binary
scaling in d-Au and Au-Au collisions at RHIC. In d-Au collisions, a suppression
in $J/\psi$ production has been observed at the forward rapidity (d direction),
at the backward rapidity (Au direction), $J/\psi$ production seems strongly
dependent on collisions centrality. The implications of heavy flavor production
in cold (d-Au) and hot (Au-Au) nuclear media at RHIC are discussed.
