The NuTeV Collaboration reported a value of sin 2 θ w measured in neutrino-nucleon deep inelastic scattering, and found that the value is three standard deviations from the standard model prediction. This result is obtained under the assumption that the strange quark-antiquark sea of nucleons are symmetric, and that the up and down quark distributions are symmetric with the simultaneous interchange of u d and p n. We discuss the contribution of asymmetric strange-antistrange sea to the Paschos-Wolfenstein relation in the extraction of weak mixing angle sin 2 θ w . We also point out that the contribution of asymmetric strange-antistrange sea should remove roughly 30-80% of the discrepancy between the NuTeV result and other determinations of sin 2 θ w when using the light-cone meson-baryon model to calculate the contribution of the strange-antistrange sea.