Immediate effects of two doses of gel-forming polymer Stockosorb (0.5 g kg-1 and 1 g kg-1) on water and air properties of Haplic Luvisols developed from loess, subjected to surface water erosion, were investigated in a field experiment. Investigated soils represented slightly and severely eroded soil. Stockosorb is a crosslinked copolymer of polyacrylamide and potassium polyacrylate. The results obtained prove that application of these doses of polymer caused significant decrease of bulk density and significant increase of maximum water capacity, saturated hydraulic conductivity, total porosity and air permeability in surface layer of investigated soils. Most effective was the rate of 1 g kg-1 of hydrogel which also resulted in a significant increase in actual moisture of soils, field water capacity and retention of useful water for plants.