The magnetic phase diagram of a two-dimensional generalized Hubbard model proposed for manganites is studied within Hartree-Fock approximation. In this model the hopping matrix includes anisotropic diagonal hopping matrix elements as well as off-diagonal elements. The antiferromagnetic (AF), ferromagnetic (F), canted (C) and paramagnetic (P) states are included in the analysis as possible phases. It is found that away from half-filling only the canted and F states may exist and AF and P states

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... hich are possible for the usual Hubbard model do not appear. This is because the F order has already developed for on-site repulsion U=0 due to the hopping matrix of the generalized model. When applied for manganites the orbital degree is described by a pseudospin. Thus our "magnetic" phase diagram obtained physically describes how orbital order changes with U and with doping for manganites. Part of our results are consistent with other numerical calculations and some experiments.