<p>Ammonia is a cornerstone of global agriculture and is expected to become a carbon-neutral energy carrier. The high-energy-consuming Haber-Bosch method and the widespread nitrate pollution in water bodies have presented severe energy and environmental challenges. Electrocatalytic nitrate reduction reaction (NO₃RR) is an attractive protocol that combines wastewater treatment with green ammonia synthesis. Transition metal phosphides (TMPs) demonstrate pronounced catalytic activity and selectivity in NO₃RR due to their controllable electronic structure and high conductivity. This review outlines the progress in the application of TMP catalysts in NO₃RR. The reaction mechanisms of introducing phosphorus to regulate the <i>d</i>-band center of the active metal for optimizing the reaction pathways are discussed. The key synthesis methods including gas-solid/solid-state reactions, liquid-phase synthesis and electrodeposition are showcased, along with their regulatory effects on the morphology of the catalysts. Based on the performance analysis of various TMP catalysts, such as Fe, Co, Ni, and Cu for NO₃RR, strategies for enhancing the ammonia yield rate and Faradaic efficiency through element doping and interface engineering are explored. Finally, the challenges in constructing stable and high-performance TMP catalysts and future development directions are depicted.</p>