We calculate the branching ratios of the hadronic Λ_b decays to η and η^' in the factorization approximation where the form factors are estimated via QCD sum rules and the pole model. Our results indicate that, contrary to B→ Kη^(') decays, the branching ratios for Λ_b→Λη and Λ_b→Λη^' are more or less the same in the hadronic Λ_b transitions. We estimate the branching ratio of Λ_b→Λη^(') to be 10.80 (10.32)× 10^-6 in QCD sum rules, and 2.78 (2.96)× 10^-6 in the pole model. We also estimate the

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... onfactorizable gluon fusion contribution to Λ_b→Λη^' decay by dividing this process into strong and weak vertices. Our results point to an enhancement of more than an order of magnitude due to this mechanism.