Sodium polyacrylate was synthesized with acrylic acid as the monomer, and sodium bisulfate and ammonium persulfate as the initiator, by means of aqueous solution polymerization. The factors influencing the properties of moisture absorption, such as monomer concentration, dosage of initiator, and reaction temperature were systematically investigated. The experimental results indicate that the moisture-absorbing property of this polymer was better than other traditional material, such as silica gel, and molecular sieve. The best reaction condition and formula are based on the orthogonal experiment design. The optimum moisture absorbency of sodium polyacrylate reaches 1.01 g/g. The mathematical correlation of this polymer with various factors and moisture absorbency is obtained based on the multiple regression analysis. The moisture content intuitive analysis table shows that neutralization degree has the most significant influence on moisture absorbency, followed by monomer concentration and reaction temperature, while other factors have less influence. Sodium polyacrylate was synthesized with acrylic acid as the monomer, and sodium bisulfate and ammonium persulfate as the initiator, by means of aqueous solution polymerization. The factors influencing the properties of moisture absorption, such as monomer concentration, dosage of initiator, and reaction temperature were systematically investigated. The experimental results that that the moisture-absorbing property of this polymer was better than other traditional material, such as silica gel, and molecular sieve. The optimum reaction condition and formula are based on the orthogonal experiment design. The optimum moisture absorbency of sodium polyacrylate reaches 1.01 g / g. The mathematical correlation of this polymer with various factors and moisture absorbency is obtained based on the multiple regression analysis. The moisture content intuitive analysis table shows that the neutralization degree has the most significant influence on moisture absorbency, followed by monomer concentration and reaction temperature, while other factors have less influence.