Metal alloys‐structured electrocatalysts (MAECs) have made essential contributions to accelerating the practical applications of electrocatalytic devices in renewable energy systems. However, due to the complex atomic structures, varied electronic states, and abundant supports, precisely decoding the metal‐metal interactions and structure‐activity relationships of MAECs still confronts great challenges, which is critical to direct the future engineering and optimization of MAECs. Here, this timely review comprehensively summarizes the latest advances in creating the MAECs, including the metal‐metal interactions, coordination microenvironments, and structure‐activity relationships. First, the fundamental classification, design, characterization, and structural reconstruction of MAECs are outlined. Then, the electrocatalytic merits and modulation strategies of recent breakthroughs for noble and non‐noble metal‐structured MAECs have been thoroughly discussed, such as solid solution alloys, intermetallic alloys, and single‐atom alloys. Particularly, we give unique insights into the bond interactions, theoretical understanding, and operando techniques for mechanism disclosure. Thereafter, we discuss the current states of diverse MAECs with a unique focus on structural property‐reactivity relationships, reaction pathways, and performance comparisons. Finally, the future challenges and perspectives for MAECs are systematically discussed. We believe that this comprehensive review will offer a substantial impact on stimulating the widespread utilization of metal alloys‐structured materials in electrocatalysis.This article is protected by copyright. All rights reserved