The energy crisis put forward higher requirements for the development of sustainable energy systems, and the production of green hydrogen by electrochemical water electrolysis is one of the important ways to achieve this goal. Transition metal amorphous alloys have been widely investigated as efficient electrocatalysts for water electrolysis. However, the low catalytic activity, high cost, lack of multifunction, poor stability, and unclear catalytic mechanism on amorphous alloy electrocatalysts have severely limited their efficiency. In this review, we summarize the recent progress on amorphous alloys. Specifically, the characteristics, structure, and preparation methods of amorphous alloys and their application, especially in water electrolysis, are discussed in detail. On the basis of the function-oriented design and the solution of key problems, the electrocatalytic performance has been effectively improved in quantity and quality. In the future, studies should focus on the aspects of controlling material morphology, element doping, composite structure, and interface characteristics, as well as the structure-activity relationship and synergetic effect. This review is of great significance to promote the study of structural design, structure-activity relationship, efficiency improvement, and catalytic mechanisms in electrocatalysis.