a How to develop cost-effective electrocatalysts for oxygen evolution reaction (OER) is one of the critical issues in renewable energy storage and conversion technology. Here, we report the preparation of well-ordered ultrathin films (UTFs) electrodes based on layered double hydroxide nanosheets (LDH NSs) and Iron porphyrin (Fe-PP) through an electrostatic layer-by-layer (LBL) technique, which shows excellent OER performance. By virtue the high catalytic activity of LDH NSs and good electron transfer ability of Fe-PP, the resulting CoNi-LDH NSs/Fe-PP UTF exhibits a remarkably low overpotential (264 mV) to attain OER current density of 10 mA cm −2 and a substantially decreased Tafel slope of 37.6 mV dec −1 , much superior to that of IrO2 catalyst. Moreover, this method can be extended to the preparation other UTFs based on LDHs and Fe-PP (e.g., CoMn-LDH NSs/Fe-PP, CoFe-LDH NSs/Fe-PP and ZnCo-LDH NSs/Fe-PP) with significantly enhanced OER performance relative to pristine LDHs NSs. To illustrate the advantage of these UTFs in practical water splitting, a prototype electrolyzer cell is also fabricated by using (CoNi-LDH/Fe-PP)30 UTF as anode and Pt wire as cathode, which achieves the production of both oxygen and hydrogen by using 1.5 V AA battery as power source.