Abstract:  Active carbon supported Au-Pt catalyst (Au-Pt/C) with different Pt/Au atom ratios was prepared and the effect of Pt/Au atom ratio on the electrocatalytic performance of Au-Pt/C in direct formic acid fuel cell (DFAFC) like the oxygen reduction ability and tolerance to formic acid was investigated. Comparing with Au/C catalyst, the Au-Pt/C catalyst exhibits better electrocatalytic performance towards the reduction of oxygen. With the increase of Pt/Au atom ratio from 0/50 to 2/48, Au-Pt/C catalyst shows excellent electrocatalytic ability and formic acid tolerance. However, when Pt/Au atom ratio is further raised to 3/47, the formic acid tolerance of Au-Pt/C is decreased. As a result, Au-Pt/C catalyst with a Pt/Au atom ratio of 2/48 is appropriate as the cathodic catalyst in DFAFC.