This study systematically investigates the impact of externally added waste wood on the reduction behavior of biocarbon-containing pellets during roasting in a rotary kiln. Experimental analyses focused on understanding the effects of key parameters such as carbon addition amount, roasting temperature, and roasting duration on pellet compressive strength, metallization rate, and kiln ring formation. The findings indicate that biochar generated by the pyrolysis of externally added waste wood significantly enhances the reduction reactions in pellets and effectively reduces ring formation tendencies. Industrial computed tomography (CT) was employed to precisely characterize the three-dimensional pore structures of roasted pellets, while scanning electron microscopy (SEM) and X-ray diffraction (XRD) analyses provided insights into the microstructural characteristics and crystal structures of pellets, elucidating the microscopic mechanisms by which external carbon addition improves pellet properties and inhibits ring formation. Based on these experimental outcomes, the study proposes optimized process parameters suitable for low-carbon ironmaking technology, offering theoretical and technical support for achieving low-carbon and sustainable transformation in the steel industry.