The objective of the studies was to compare optimum moisture content determined with Proctor's method with other moisture properties of the selected soils from the region of Szczecin Lowland (Poland). Soils of the 1st and 2nd complex of agricultural usefulness were investigated by measurements conducted on soil samples collected outside of headlands and technological routes. In the subsoil the following soil properties were determined: current field moisture content, soil moisture at water potentials pF0 and pF2, granulometric composition, density of solid phase, humus content, reaction, limits of plasticity and liquidity, maximum dry density of solid particles and optimal moisture content determined with Proctor's apparatus. It was proved that variability of optimal moisture value increases along with the increase of loamy fractions. It was also found out that for soils of the sandy loam or sandy clay loam granulometric composition the optimal moisture content of soil, determined with Proctor's apparatus is similar to the value of its optimum water content for tillage.