In the present paper, we explore the electrocatalytic activity of the glassy carbon (GC) electrode modified with Sn–Pd bimetallic electrocatalysts, i.e., Sn was electrochemically deposited on the GC electrode premodified by electrodeposition of Pd, toward the oxygen reduction reaction (ORR). The results demonstrate that the in situ underpotential deposition of Sn onto the GC electrode, premodified by an optimized amount of electrodeposited Pd, enhance the electrocatalytic activity of the electrode to such an extent that an exclusive one-step four-electron ORR takes place at a considerably lower overpotential. The mechanistic idea for the observed enhanced ORR at the Sn–Pd bimetallic electrocatalyst is also presented based on the ligand effect of Sn. The experimental investigations were performed using cyclic, steady-state voltammetric, and open-circuit potential measurement techniques.