A stable pillared-layer metal-organic framework (MOF) was obtained through post-synthesis modification from an unstable fence-like MOF for the first time. By virtue of high exposure of active sites on the layers, the evolved MOF with Fe doping exhibits an ultralow overpotential of 238 mV at 10 mA cm-2 during the oxygen evolution reaction (OER). Moreover, it shows a superior electrocatalytic stability with almost no attenuation for more than 168 h.