Herein, we report a heterogeneous, aerobic, additive-free and environmentally benign catalytic protocol for oxidative aromatization of saturated nitrogen-heterocycles using a mesoporous manganese oxide material. The aromatized products can be separated by easy filtration and the catalyst is reusable for at least four cycles. Mechanistic investigation provides evidence for radical intermediates, a multi-electron redox cycle between Mn centers, and an oxygen exchange mechanism.