Specific features of polyelectrolyte behavior and structure of the sodium polyacrylamido-2-methyl-1-propanesulfonate cryogels were studied. The cryogels were synthesized in frozen aqueous solutions at -15 degrees C, the reference gels - at 25 degrees C. It was shown that the polyelectrolyte swelling of cryogels is much weaker than that of gels synthesized in solutions. The ethanol-induced collapse of both gels and cryogels occurs stepwise at similar ethanol concentrations. The high-porosity structure of the cryogels is preserved in the collapsed state. The small-angle X-ray scattering (SAXS) spectra show maxima corresponding to ordered inhomogeneities of 0.5-3.0 nm scale. The positions of the observed maxima depend on the conditions of the synthesis and on the concentration of the polymer in the gels and cryogels. (C) 2016 Published by Elsevier Ltd.