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The oxygen reduction reaction (ORR) activity of PtNi alloys is easily decreased on account of the Ni leaching under the harsh acidic environment. Therefore, we prepared a PtNi1.5-(CeO2)0.8/C electrocatalyst with abundant PtNi1.5-(CeO2)0.8interfaces by a wet-chemical synthesis strategy. Electrochemical tests revealed that PtNi1.5-(CeO2)0.8/C exhibits excellent ORR performance with mass activity (MA) of 551.1 mA mgPt−1and specific activity (SA) of 1.3 mA cmPt−2@ 0.9 V vs. RHE, respectively, which are better than commercial JM Pt/C (MA of 152.9 mA mgPt−1and SA of 0.2 mA cmPt−2@ 0.9 V vs. RHE). More interestingly, it displays remarkable durability with 9.0% of its initial MA loss after 10,000 CV cycles, outperforming JM Pt/C (a 15.1% loss) and PtNi1.5/C counterparts (a 35.5% loss). The density functional theory (DFT) calculations explained that the electronic interaction at interfaces leads to a lower d-band center (εd) and weaker oxygen adsorption energy E(ads)(O) in Pt atoms of PtNi1.5-(CeO2)0.8than that in Pt NPs, which is favorable for the desorption of O* and promotes the ORR process. Furthermore, the diffusion energy barrier E(FS-IS)of Ni atoms in PtNi1.5-(CeO2)0.8from subsurface to surface is higher than that in PtNi1.5counterparts, indicating the Ni leaching can be decelerated.