C5A (Q²) axial form factor is extracted from the ANL neutrino-deuteron scattering data with deuteron structure e?ects taken into consideration. The best fit of the C5A(Q²) axial form factor is obtained assuming dipole parametrization with C5A (0) = 1.13 ± 0.15 and MA = 0.94 ± 0.08 GeV.