MoxRuySez-(CO)(n) electrocatalyst was prepared by a chemical pyrolysis of Ru-3(CO)(12) + Mo(CO)(6) + Se mixture at 140 degrees C and sintering in Se atmosphere in a tubular furnace at 250 degrees C. The catalyst was characterized using techniques such as XRD (X-ray diffraction) SEM (scanning electron microscopy), TEM (transmission electron microscopy), voltametry and polarization (current-potential) measurements. The results indicated that chemically synthesized MoxRuySez-(CO)(n) is near amorphous in nature and possesses appreciable catalytic activity for oxygen reduction reaction in a polymer electrolyte (nafion membrane) fuel cell. The electrocatalytic activity seems to diminish with Se incorporation in the lattice of the Mo-Ru-carbonyl clusters formed during synthesis.