Disclosed are a catalyst complex and a method of manufacturing the same. The catalyst complex may be manufactured by uniformly depositing metal catalyst particles on pretreated support particles through an atomic layer deposition process using a fluidized-bed reactor, which may be then uniformly dispersed throughout the ionomer solution. As such, manufacturing costs may be reduced due to the use of a small amount of metal catalyst particles and the durability of an electrolyte membrane and OCV may increase. Further disclosed are a method of manufacturing the catalyst complex, an electrolyte membrane including the catalyst complex, and a method of manufacturing the electrolyte membrane.