Cellulose-based hydrogels (CBHs) are natural hydrogels with excellent biocompatibility, degradability, and environmental friendliness, making them widely applied in environmental science. Through modification and optimization, CBHs exhibit enhanced adsorption capacities and efficient removal of pollutants, particularly in removing harmful substances such as pharmaceuticals, dyes, and heavy metals from water, as well as their use in soil remediation and environmental sensor design. This chapter focuses on the preparation methods and modification strategies of CBHs, exploring their application prospects in environmental protection, particularly in water pollution control and soil remediation. Additionally, a comparative analysis of the sustainability of CBHs with gelatin-based hydrogels and polyurethane hydrogels is presented, evaluating the performance and application value of different materials in environmental science. This chapter provides essential theoretical support and practical guidance for the development of efficient and sustainable environmental remediation materials.