This paper reports synthesis and hydrophilicity of hydroxylated poly(acrylamides), in which one, three, and six hydroxyl groups were attached to the terminal of their side chains, respectively : poly(a-hydroxyethyl acrylamide), poly(N-[tris(hydroxymethyl)methyl] acrylamide), and poly(N,N-di(N-[tris(hydroxymethyl)methyl]-2-acetamido) acrylamide). The initial hypothesis of molecular design of a very hydrophilic polymer was that hydrophilicity increases with an increase in the number of hydroxyl groups per repeating unit due to the enhanced shielding effect on hydrophobic main chains. Contrary to expectations, the relative hydrophilicity of these polymers, determined from the surface tension of these aqueous solutions, tended to decrease with an increase in the number of hydroxyl groups per repeating unit. As the number of hydroxyl groups per repeating unit increased, the chain mobility of the methylene groups adjacent to the terminal hydroxyl groups (determined from the spin-lattice relaxation time (T-1) measurement) was restricted, the fraction of bound water (determined from the DSC measurement) was decreased, and the proton-deuterium exchange rate of hydroxyl groups in D2O-DMSO-d(6) (DMSO-d(6) = dimethyl sulfoxide-d(6)) mixed solution (determined from H-1 NMR spectroscopic measurement) was decreased. These results indicate that the degree of intramolecular hydrogen bonding of the hydroxyl groups is enhanced with an increase in the number of hydroxyl groups per repeating unit, which eventually reduces the hydrogen bonding with water, resulting in a reduction of the hydrophilicity.