Through a large number of static experiments in l ab oratory, this paper is intend to study the compound polyacrylamide gel system un der adding polyacrylamide or amphoteric polyacrylamide, we study some factors w hich influence quality of gel system, which include the concentration of the negative polyacrylamide and cation polyacrylamide, the concentration of cross- linker and PH of the gel system. Through analysizing and comparing the gel time and the strength, the best condition of compound gel system can be chosed.