Hydrotalcite/poly(sodium acrylate-acrylamide) composite was synthesized by using inverse suspension polymerization method under different hydrotalcite content, neutralization degree and ratio of monomer with orthogonal experiments. The surface morphology, structure and humidity controlling properties of composite were observed and determined. The results show that hydrotalcite/poly (sodium acrylate-acrylamide) composite is in an irregular block like structure with different size. During the polymerization process, acrylate and acrylamide monomers are successfully intercalated into the interlayer of hydrotalcite, and the distance of (003) hydrotalcite plane is increased from 0.766nm to 1.146nm. The impact of three factors on the humidity controlling behavior of composites increases by the order of ratio of monomer, hydrotalcite content and neutralization degree. The optimum preparation parameters are hydrotalcite content of 4%, neutralization degree of 90% and ratio of monomer in 9:1.