AbstractElectrocatalytic nitrogen reduction reaction (NRR) represents a promising sustainable approach for NH3synthesis. However, the poor NRR performance of electrocatalysts is a great challenge at this stage, mainly owing to their low activity and the competitive hydrogen evolution reaction (HER). Herein, 2D ferric covalent organic framework/MXene (COF‐Fe/MXene) nanosheets with controllable hydrophobic behaviors are successfully prepared via a multiple‐in‐one synthetic strategy. The boosting hydrophobicity of COF‐Fe/MXene can effectively repel water molecules to inhibit the HER for enhanced NRR performances. By virtue of the ultrathin nanostructure, well‐defined single Fe sites, nitrogen enrichment effect, and high hydrophobicity, the 1H,1H,2H,2H‐perfluorodecanethiol modified COF‐Fe/MXene hybrid shows a NH3yield of 41.8 µg h−1mgcat.−1and a Faradaic efficiency of 43.1% at −0.5 V versus RHE in a 0.1mNa2SO4water solution, which are vastly superior to the known Fe‐based catalysts and even to the noble metal catalysts. This work provides a universal strategy to design and synthesis of non‐precious metal electrocatalysts for high‐efficiency N2reduction to NH3.