2-Acrylamido-2-methyl propane sulfonic acid is a kind of vinyl monomer that contains sulfonic acid gene. with sound performances of complexation, absorption, bioactivity, surface activity. hydrolysis and heat stability, in the aqueous solutions, its hydrolytic speed is low, and its sodium salt has sound performance of anti-hydrolysis under the term of high PH value. Under the term of acidity, the performance of anti-hydrolysis of its multipolymer is far higher than that of polyacrylamide.