The addition of carriers to anaerobic digestion (AD) systems to provide spatial structures and colonization sites for microorganisms, thereby enhancing community stability and biogas potential, is a focal point of current research. However, when selecting novel carrier materials, it is imperative to first evaluate their toxicological impacts and potential inhibitory effects on the methanogenic process. Through a fed-batch fermentation mode, the effects of AB silicone at five different dosage concentrations (2% , 5% , 10% , 15% , and 20%) on the cellulose degradation and methanogenesis process were investigated, to evaluate the feasibility of utilizing this AB silicone as a carrier material. The results demonstrated that the addition of AB silicone led to a significant decrease in the CH4 yield, with the 2% dosage exhibiting the most pronounced inhibitory effect on methanogenesis. Across the three consecutive experimental rounds, the cumulative CH4 production was decreased by 41.3% , 31.8% , and 31.1% , respectively. The relative abundance of the dominant hydrolytic bacteria Bacillota (Firmicutes) was decreased from 69.7% to 57.9% , whereas that of Synergistota was increased from 10.8% to 15.7%. Furthermore, the relative abundances of Methanosarcina and Methanoculleus declined from 15.4% and 2.4% to 10.0% and 1.4%, respectively. Distinct from typical chemical inhibition, neither terminal accumulation of volatile fatty acids (VFAs) nor pH instability was observed during the experiment, indicating that the inhibitory effect likely did not stem from toxicity to the methanogenic consortia, but possibly because the organic silicone filled a portion of the volume, hindering the contact between microorganisms and cellulose, which led to a portion of the cellulose remaining undegraded. Specific methanogenic activity ( SMA) assays conducted on the residual fermentation digestate after the three rounds of experiments revealed that the half-maximal inhibitory concentration (IC50) of AB silicone on the SMA was 1.8%.