Due to the change of the intra- and intermolecular hydrophobic association with the concentration of hydrophobic association polymer solution, the result of intrinsic viscosity for the hydrophobic association polymer tested according to the method in the national standard (GB12005.1-89), could not accurately reflect the single chain character. In this study, based on the inclusion of cyclodextrin and hydrophobes, the intrinsic viscosities of hydrophobic association polymer solution with various molar ratios of cyclodextrin and hydrophobes (CD: [H]) were measured by capillary method and calculated by one point and extrapolation method respectively. The results obtained by the two methods are consistent with each other. With the increase of CD: [H], the intrinsic viscosity of the hydrophobic associating polymer increased and then stabilized, and the Flory-Huggins interaction parameter decreased and then tended to plateau. The results of comparison experiment show that the intrinsic viscosities of the hydrophobic associating polymer change by the inclusion of cyclodextrin with hydrophobes, and the excess cyclodextrin has little effect on the conformation of polymer backbone. Key words：intrinsic viscosity; hydrophobic association polymer; cyclodextrin; polyelectrolyte effect