Tuning the morphology and compositions of catalyst is an effective method for promoting electrocatalytic intrinsic activity. However, many newly-generated nanocrystals with better nanostructures often have a large size, which enforces them to display extremely limited surface area and ultimately lead to the limited electrocatalytic activity. To break this bottleneck, we herein report a facile and reproducible wet-chemical method to control the synthesis of a class of ultra-uniform and small PdBi nanodots endowed with both high surface areas and tunable compositions. The presented PdBi nanodots show the ultrasmall size (ca.2.5 nm) and great uniform dispersion property. These significant characteristics enable them to exhibit unprecedented electrocatalytic activities and durability toward formic acid oxidation. The mass activity and electrochemical surface active (ECSA) of prepared PdBi nanodots for the formic acid oxidation is 8.9/3.75 times higher than that of commercial Pd/C, respectively. We speculate that both of this facile synthetic approach and remarkable electrocatalytic performance of the obtained catalysts in this work illustrate that they can be applied as a promising catalyst for direct formic acid cells. (C) 2017 Elsevier B.V. All rights reserved.