The electronic structure and intrinsic anomalous Hall conductivity of nickel have been calculated based on the generalized gradient approximation (GGA) plus on-site Coulomb interaction (GGA + ) scheme. The highly accurate all-electron full-potential linearized augmented plane-wave method is used. It is found that the intrinsic anomalous Hall conductivity () obtained from the GGA + calculations with eV and eV is in nearly perfect agreement with that measured recently at low temperatures while, in contrast, the from the GGA calculations is about 100 larger than the measured one. This indicates that, as for the other spin-orbit interaction (SOI)-induced phenomena in 3 itinerant magnets, such as the orbital magnetic magnetization and magnetocrystalline anisotropy, the on-site electron-electron correlation, though moderate only, should be taken into account properly in order to get the correct anomalous Hall conductivity. The intrinsic and the number of valence electrons () have also been calculated as a function of the Fermi energy (). A sign change is predicted at eV (), and this explains qualitatively why the theoretical and experimental values for Fe and Co are positive. It is also predicted that fcc NiCo(Fe,Cu) alloys with being small would also have the negative with the magnitude being in the range of 500–1400 cm. The most pronounced effect of including the on-site Coulomb interaction is that all the -dominant bands are lowered in energy relative to the by about 0.3 eV, and consequently, the small minority spin hole pocket disappears. The presence of the small hole pocket in the GGA calculations is attributed to be responsible for the large discrepancy in the between theory and experiment.