In this work, La2NiO4+δ–xCe0.55La0.45O2–δ (denoted as LNO–xLDC) with various LDC contents (x = 0, 10, 20, 30, and 40 wt%) were prepared and evaluated as bifunctional oxygen electrodes for reversible solid oxide cells (RSOCs). Compared with the pure LNO, the optimum composition of LNO–30LDC exhibited the lowest polarization resistance (Rp) of 0.53 and 0.12 ?·cm2 in air at 650 and 750 ℃, respectively. The enhanced electrochemical performance of LNO–30LDC oxygen electrode was mainly attributed to the extended triple phase boundary and more oxygen ionic transfer channels. The hydrogen electrode supported single cell with LNO–30LDC oxygen electrode displayed peak power densities of 276, 401, and 521 mW·cm–2 at 700, 750, and 800 ℃, respectively. Moreover, the electrolysis current density of the single cell demonstrated 526.39 mA·cm–2 under 1.5 V at 800 ℃, and the corresponding hydrogen production rate was 220.03 mL·cm–2·h–1. The encouraging results indicated that LNO–30LDC was a promising bifunctional oxygen electrode material for RSOCs.