Precious metals exhibit superior catalytic properties because of their special structures.On the other hand,bimetal or multi-metal catalysts have higher activity and selectivity than mono-metal counterparts because of the synergy of metals.Therefore,the preparation and catalytic performance of bimetal or multi-metal catalysts have attracted much attention.In this thesis,Pt/Au bimetallic nanoparticles were prepared by reduction using sodium borohydride.TEM and UV absorption spectrum results demonstrated that the structure of catalyst is bimetallic nanoparticles of Au modified by Pt.Hydrogenation of butanal was used as the reaction to verify the catalytic property of thePt/Au bimetallic nano-catalyst.The effects of different Pt/Au molar ratios and the reaction temperatures on the catalytic hydrogenation of butanal were examined.It was found that the catalyst with n(Au):n(Pt)=1:5 exhibited best catalytic activity.The best temperature was 40 ℃.