The development of low-cost, efficient, noble-metal-free electrocatalysts for the oxygen evolution reaction (OER) is important for renewable energy conversion. We prepared hierarchical hollow NiCoMn-layered double hydroxide (LDH) microcuboids that consisted of two dimensional (2D) nanosheets by using a solvothermal method. The prepared Ni 6 Co 11 Mn-LDH exhibits high OER activity, with an overpotential of 248 mV at a current density of 10 mA cm À 2 and a small Tafel slope of 72.2 mV dec À 1 , which is even better than the noble-metal RuO 2 catalyst. It remains stable after chronopotentiometric testing at a high current density of 100 mA cm À 2 for 22 h, indicating potential for practical application. The enhanced OER performance is ascribed to the transition of Ni 2 + to Ni 3 + in NiCo-LDH induced by Mn doping, which activates the Ni sites. This work provides an approach to further optimize the OER performance of NiCo-LDH based catalysts.