Metal borides have been acknowledged as promising candidates for alkaline oxygen evolution reaction (OER). Here, amorphous ternary metal borides (Ni-Ce-B) with different molar ratios of Ce% are achieved by a facile wet chemical method. With the optimal 5% of Ce, the as-prepared Ni-Ce-B-5/NF electrode exhibits comparable OER performance with lower overpotential (240 mV) than that of pure Ni-B/NF electrode (330 mV) and other metal borides. The high activity of Ni-Ce-B/NF is attributed to the amorphous structure and synergistic effect of binary metal Ni and Ce in Ni-Ce-B materials. Additionally, CeO2-x forms and serves as an electron acceptor during the self-electrooxidation process, facilitating the formation of crystalline high-valence nickel species, resulting in robust electrocatalysis and long-term stability. This work presents a Ce-based metal boride as a promising candidate for the low-cost and highly efficient OER catalyst.