A facile method for the preparation of sodium alginate(SA)/carboxyl-functionalized graphene(G-COOH)composite hydrogel was developed. Based on the coordination ability of lanthanide ions to the carboxyl groups, a series of hydrogel derived from different ratios of SA and G-COOH was fabricated by neodymium(Nd~(3+)) ions coordination. A relatively uniform layered structure was recorded by SEM at the interior of SA/G-COOH hydrogel. Several parameters such as water content, swelling ratio(SR), tensile test and solvent resistance were also investigated. The SA/G-COOH composite hydrogel showed excellent mechanical strength, and the tensile strength of SA/G-COOH composite hydrogel reaches 53.72 MPa at high water content. Due to the coordination ability of Nd~(3+) ions, the hydrogel also exhibited an excellent solvent resistance and stability. A facile method for the preparation of sodium alginate (SA) / carboxyl-functionalized graphene (G-COOH) composite hydrogel was developed. Based on the coordination ability of lanthanide ions to the carboxyl groups, a series of hydrogel derived from different ratios of SA A relatively uniform layered structure was recorded by SEM at the interior of SA / G-COOH hydrogel. Several parameters such as water content, swelling ratio (SR The SA / G-COOH composite hydrogel showed excellent mechanical strength, and the tensile strength of SA / G-COOH composite hydrogel reaches 53.72 MPa at high water content. Due to the coordination ability of Nd ~ (3+) ions, the hydrogel also exhibited an excellent solvent resistance and stability.