[en] Considering the constraints on model parameters from the latest experimental data, we study the contributions of new gauge boson W^' predicted by the general 221 models to the radiative leptonic decays of charged B and D mesons. It is found that the largest contributions of W^' in the non-universal 221 model to the branching fractions occur in the decay modes B^- → γμ^- anti ν_μ and B^- → γτ^- anti ν_τ, which can reach to about 8 % of the corresponding SM values in the up-quark mixing scenario. In contrast, the relative corrections of W^' predicted by the un-unified 221 model to the branching fractions are very tiny and identical for all the decay modes. (orig.)