Abstract: In this paper, releasing patterns of Cr³⁺ from the particles of package cross-linking agent in water are investigated by using self-made PAM hydrophilic resin particles. And a physical model of Cr(III) released from the particles of package cross-linking agent was finally constructed. In addition, the properties of the package cross-linking agent being gelatinized into HAPM are studied and the new technology of HPAM gelatin controlled-crosslinking is explored in this paper.