  We theoretically and numerically show that longitudinal orbital currents in
ferromagnets depend on the magnetization direction, which contribute to the
anisotropic magnetoresistance (AMR). This orbital contribution to AMR arises
from the momentum-dependent orbital splitting, which is generally present in
multi-orbital systems through the orbital anisotropy and the orbital
hybridization. We highlight the latter orbital hybridization as an unrecognized
origin of AMR and also as a common origin of AMR and orbital Hall effect.
