QCD analysis of the CCFR data for $xF_3$ and Higher--Twist Contribution

The QCD analysis of the $xF_3$ structure function measured in deep-inelastic scattering of neutrinos and antineutrinos on an iron target at the Fermilab Tevatron is done in 1--, 2-- and 3--loop order of QCD. The x dependence of the higher--twist contribution is evaluated. The experimental value of higher--twist corrections to the Gross--Llewellyn Smith sum rule is discussed.