This study focuses on investigating the intrinsic kinetics of methane steam reforming over a lanthanum promoted Ru/La-Al₂O₃ catalyst at low temperatures ranging from 475 to 550 °C and 140 kPa. To facilitate the research, high-throughput experimentation was employed using 16 integral fixed bed reactors. The steam reforming reaction was influenced by co-reactants and products. In this work, we proposed a reaction mechanism and developed a kinetic model to understand the underlying process. The findings indicate that methane dissociative adsorption is the rate-determining step, and CO is identified as the most abundant surface intermediate. The developed kinetic model not only provides the best fit to the experimental data but also statistically significant and thermodynamically consistent.