Abstract: Polyacrylamide (PAM) and its hydrolysed product (HPAM) were studied viscosime-trically in aqueous solution of 1, 0.5, 0, 1, 0.025 and 0.01N NaNO₃. A linear relationship between tga (see Fig. 1) and degree of hydrolysis (DH%) was found with the same concentration of added salt (C_s) and the same molecular weight of poly-mers. It was also found that the intrinsic viscosity [η] of PAM and HPAM is propor-tional to the C₃^-1/2. The same [η]_∞ values of samples were obtained when the polymer has the same initial molecular weight, but different DH%.