Among　the　current　industrial　hydrogen　production　technologies,　electrolysis　has　attracted　widespread　attention　due　to　its　zero　carbon　emissions　and　sustainability.　However,　the　existence　of　overpotential　caused　by　reaction　activation,　mass/charge　transfer,　etc.　makes　the　actual　water　splitting　voltage　higher　than　the　theoretical　value,　severely　limiting　the　industrial　application　of　this　technology.　Therefore,　it　is　particularly　important　to　design　and　develop　highly　efficient　electrocatalysts　to　reduce　overpotential　and　improve　energy　efficiency.　Among　the　various　synthesis　methods　of　electrocatalysts,　electrochemical　synthesis　stands　out　due　to　its　simplicity,　easy　reaction　control,　and　low　cost.　This　review　article　classifies　and　summarizes　the　electrochemical　synthesis　techniques　(including　electrodeposition,　electrophoretic　deposition,　electrospinning,　anodic　oxidation,　electrochemical　intercalation,　and　electrochemical　reconstruction),　followed　by　their　application　in　the　field　of　water　electrolysis.　In　addition,　some　challenges　currently　faced　by　electrochemical　synthesis　in　electrocatalytic　hydrogen　production,　and　their　potential　solutions　are　discussed　to　promote　the　practical　application　of　electrochemical　synthesis　in　water　electrolysis.Graphical　AbstractThis　review　summarizes　and　classifies　commonly　used　electrochemical　synthesis　techniques,　followed　by　the　application　of　electrochemical　synthesis　methods　in　research　on　water　electrolysis.　Additionally,　some　challenges　faced　by　electrochemical　synthesis　in　the　field　of　water　electrolysis　and　possible　solutions　are　discussed.