Acetic acid from bio-oil is a renewable resource for hydrogen production. Layered perovskite-like Ca-doped La_2−xCa_xNiO_4±δ (x = 0, 0.5, 1, 1.5 and 2) catalysts were prepared via a sol–gel method and tested in auto-thermal reforming (ATR) of acetic acid (AC) for hydrogen production. XRD, TPR, BET, XPS, TG, SEM and TEM characterization was carried out; the results show that the layered perovskite-like structure was the main phase in La_2−xCa_xNiO_4±δ with 0 ≤ x ≤ 1, and La–Ca–O composite oxide species increased with increasing calcium content, while the reducibility of Ni metal was gradually enhanced as well. During the ATR process, La₂O₂CO₃ and CaCO₃ species were generated and nickel particles were stable, suggesting that partial substitution of La by Ca in La_2−xCa_xNiO_4±δ was beneficial to stabilizing Ni particles with less coking. As a result, over the LaCaNiO_4±δ catalyst, the AC conversion reached 100% and the hydrogen yield remained stable near 2.80 mol-H₂ per mol-AC during the ATR test.