  Experimentally, the production of oppositely charged dimuon events by
neutrino and anti-neutrino deep inelastic scattering (DIS) is used to determine
the strangeness asymmetry inside a nucleon. Here we point out that the direct
production of $D$-meson in DIS may make substantial influence to the
measurement of nucleon strange distributions. The direct $D$-meson production
is via the heavy quark recombination (HQR) and via the light quark
fragmentation from perturbative QCD (LQF-P). To see the influence precisely, we
compute the direct $D$-meson productions via HQR and LQF-P quantitatively and
estimate their corrections to the analysis of the strangeness asymmetry. The
results show that HQR has stronger effect than LQF-P does, and the former may
influence the experimental determination of the nucleon strangeness asymmetry.
