Abstract <p>Hydrogen metallurgy has emerged as a pivotal low-carbon technology driving the future of ironmaking, with fluidized bed reactors offering efficient potential for ore reduction. However, interparticle sticking during fluidization remains a critical challenge limiting process stability and scalability. This study addresses this issue by designing a side-stirred fluidized bed with an inclined agitator, systematically investigating the effects of gas composition (H₂ proportion) and gas flow rate on particle sticking behavior via single-factor experiments. Reduction degree, fluidization state, and product microstructures were analyzed using chemical analysis, pressure drop monitoring, and exhaust gas composition tracking. Under optimal conditions (33% H₂ in reducing gas, gas flow rate of 2.8 m³·h⁻¹ and 160 r·min⁻¹ agitation), a reduction degree of 93.3% and sticking ratio of 10.4% were achieved. Mechanistically, the inclined agitator combined with tailored gas parameters (hydrogen enrichment and adequate gas flow) suppressed whisker formation on reduced particles, minimized iron particle growth, and maintained bed fluidity—key to mitigating sticking. The limiting link of the hydrogen reduction process of iron ore powder in the side-stirred fluidized bed is the interfacial chemical reaction, with an apparent activation energy of 27.13&#xa0;kJ·mol⁻¹. This work provides a novel approach to stabilize fluidized bed ironmaking, with implications for advancing low-carbon metallurgical processes and reactor scale-up.</p> Graphical Abstract <p></p>