Nafion®-stabilized Pt nanoparticle colloidal solution is synthesized through ethylene glycol reduction. Pt/Nafion® added with carbon black as electric conduction material (labeled Pt/Nafion®-XC72) shows excellent electrochemical property compared with Pt/C. After a 300-cycle discharging durability test, the cell performance of membrane electrode assembly (MEA) with the Pt/Nafion®-XC72 and Pt/C catalysts indicates a 29.9% and 92.2% decrease, respectively. The charge transfer resistances of Pt/Nafion®-XC72 and Pt/C increase by 27.2% and 101.9%, respectively. The remaining electrochemically active surface area of Pt is about 61.7% in Pt/Nafion®-XC72 and about 38.1% in Pt/C after the durability test. The particle size of Pt/C increases from about 5.1 nm to about 10.8 nm but only from 3.6 nm to 5.8 nm in the case of Pt/Nafion®-XC72. These data suggest that Pt/Nafion®-XC72 as a catalyst can enhance the durability of PEMFCs compared with Pt/C.