Ethylene glycol is the core chemical stock for the manufacture of polyester and antifreeze that consumes around 20 million tonnes per year. Current industrial production suffers from large energy consumption, complicated operation, and high pollution. Herein, we prepared the Pd nano-dendritic catalyst by electrochemical deposition method for one-step electrocatalytic oxidation of ethylene to ethylene glycol. This catalyst exhibits remarkable electrocatalytic performance under ambient temperature and pressure, namely, the ethylene glycol faradaic efficiency of 62% at 1.65 V vs. the reversible hydrogen electrode (RHE) and partial current density of 1.06 mA cm−2 at 1.7 V vs. RHE. Using Ag as the dopant with Pd nano-dendritic, the faradaic efficiency and the partial current density further increased to 75.55% and 1.32 mA cm−2, respectively. Both experimental and density functional theory results reveal that Ag doping not only effectively reduces the reaction barrier but also facilitates the desorption of ethylene glycol, resulting in enhanced electrocatalytic performance.