Grafted copolymers based on natural polysaccharides are interesting from the standpoint of creating targeted drug delivery systems. The properties of graft copolymers of pullulan with side chains of poly(2-methyl-2-oxazoline) and poly(2-ethyl-2-oxazoline) are studied. The conformational and hydrodynamic characteristics of the indicated polymers, such as the coefficient of translational diffusion, characteristic viscosity, molecular weight, equilibrium rigidity, and hydrodynamic diameter of chains, are determined using nuclear magnetic resonance, dynamic light scattering, analytical ultracentrifugation, viscometry, and a number of combined techniques. Increase of the value of equilibrium rigidity of grafted polymers with poly(2-oxazoline) side chains was detected.