  We perform QCD fit of the nucleon strange and anti-strange sea distributions
to the neutrino and anti-neutrino dimuon data by the CCFR and NuTeV
collaborations, supplemented by the inclusive charged lepton-nucleon Deep
Inelastic Scattering (DIS) and Drell-Yan data. The effective semi-leptonic
charmed-hadron branching ratio is constrained from the inclusive charmed hadron
measurements performed by the FNAL-E531 and CHORUS neutrino emulsion
experiments as $B_\mu=(8.8\pm0.5)%$. We obtain a strange sea suppression factor
{$\kappa(20 {\rm GeV}^2)=0.62\pm0.04({\rm exp.})\pm0.03({\rm QCD})$}. An
$x$-distribution of total strange sea obtained in the fit is slightly softer
than the non-strange sea, and an asymmetry between strange and anti-strange
quark distributions is consistent with zero (integrated over $x$ it is equal to
{$0.0013\pm 0.0009({\rm exp.}) \pm 0.0002({\rm QCD})$ at the scale of $20 {\rm
GeV^2}$}).
