A series of polyacrylate thickening agents have been prepared by inverse emulsion polymerization. Rheological properties of the resultant polyacrylate thickening agent have been investigated. It was found that the ratio of acrylamide (AM)/acrylic acid (AA), the amount of water, crosslinking agent in the recipe affect the thixotropic index and dilution curve. In addition, reaction temperature and concentration of thickening agent have also played a great role on rheological properties.