Abstract: The structural modification of rosa sterilis pomace soluble dietary fiber (RSDF) was performed through the sulfamic acid-N, N-dimethylformamide method to obtain sulfated rosa sterilis pomace soluble dietary fiber (SSDF). The adsorption characteristics and mechanism of SSDF on nitrite, cholesterol, and three bile salts (sodium taurocholate, sodium glycochenodeoxycholate, and sodium cholate) were systematically investigated by analyzing adsorption kinetics and isothermal adsorption model under varying additions, including additive amount, adsorption times, and initial solution concentrations. The results showed that the sulfuric acid esterification modification significantly improved the adsorption capacity of SSDF for nitrite. At an addition amount of 100 mg, SSDF exhibited a higher adsorption amount (34.84 mg/g) and adsorption rate (68.94%) compared to RSDF (29.01 mg/g, 34.24%). For cholesterol adsorption, the difference between SSDF and RSDF was minimal. However, SSDF demonstrated superior performance within a short time (≤30 min). The adsorption of nitrite onto cholesterol by SSDF and RSDF was suitable to be fitted by quasi-secondary kinetics and Freundlich model. Furthermore, SSDF exhibited a better adsorption characteristic for cholate, especially for sodium cholate, achieving a maximum adsorption rate of 90.31%. The adsorption process was in accordance with the Freundlich model fitting (R²>0.9534). This study has the potential to provide theoretical insights into enhancing the adsorption capacity and utilization efficiency of soluble dietary fiber in rosa sterilis pomace. Furthermore, these results can establish a scientific foundation for the application of sulfated modified dietary fiber in human health regulation.