The inverse emulsion polymerization of acrylamide has been studied with γ-ray initiation. Polyacrylamide with super high molecular weight over ten million (11×10,6,) , which is very important in application as flocculant, is obtained. In this work, some mothods are taken to enhance the molecular weight as follows: (l) In order to prepare soluble polyacrylamide with super high molecular weight, the better conditions are: the emulsifier content is about 2% and the monomer concentration is about 20%~24% in the composition of monomer emulsion, and the absorbed dose is about 500~600Gy. (2) Initiating with high dose rate and polymerizing with low dose rate can not only enhance the molecular weight of product, but also curtail the polymerizing time. (3) Stopping radiation when the conversion gets to about 10% and post-polymerizing outside the radiation source until the conversion gets to 82% can obtain polyacrylamide with super high molecular weight, and shorten the irradiation time as well.