The elastomers of polyvinyl. alcohol gel were made from the polyvinyl alcohol polymer, with boric acid added as a crosslinking agent, in the mixed solvent of dimethyl sulfoxide and water. From the experimental results, the viscosity of polyvinyl alcohol solution is found to increase not only with an increment of boric acid content, but also with the temperature in the range of 70 degrees C similar to 100 degrees C, although the viscosity is decreased in the range of 30 degrees C similar to 70 degrees C. Moreover, the molecular mass between junctions of polyvinyl alcohol gel is calculated from the rubber elastic theory and found to be decreased with the increment of boric acid content. We also evaluated the values of Young＇s modulus of polyvinyl alcohol gel, E, E*, and the elastic parameters C-1 and C-2 of the Mooney-Rivlin equation, according to Hook＇s law and theory of rubber elasticity. Based on these, the polyvinyl alcohol gel behaves as a goad rubberlike elastic property.