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For lignin valorization, simultaneously achieving the efficient cleavage of ether bonds and restraining the condensation of the formed fragments represents a challenge thus far. Herein, we report a two-step oxidation–hydrogenation strategy to achieve this goal. In the oxidation step, the O₂/NaNO₂/DDQ/NHPI system selectively oxidizes C_αH–OH to C_αO within the β-O-4 structure. In the subsequent hydrogenation step, the α-O-4 and the preoxidized β-O-4 structures are further hydrogenated over a NiMo sulfide catalyst, leading to the cleavage of C_β–OPh and C_α–OPh bonds. Besides the transformation of lignin model compounds, the yield of phenolic monomers from birch wood is up to 32% by using this two-step strategy. The preoxidation of C_αH–OH to C_αO not only weakens the C_β–OPh ether bond but also avoids the condensation reactions caused by the presence of C_α⁺ from dehydroxylation of C_αH–OH …