Influence of keratin-bark-urea compost on the wettability and surface free energy of brown soil was investigated. The keratin-bark-urea compost (KKM) was added to soil in doses from 5 to 50 weight percent. The thin column wicking method was used for determination of the contact angle and the surface free energy. This method is based on liquid penetration in porous solid layer deposited in a glass capillary. For this purpose measurements of the penetration rate of n-alkanes (n-octane and n-decane), water and formamide were carried out. Surface free energy components for soil with KKM were determined using Washburn equation. In general, the wicking rates for polar liquids were higher than for n-alkanes. In the case of n-octane the plots of square penetration distance (x2) versus time (t) was linear and was delimited by the corresponding plots for the check probe (i.e. for initial soil sample) and by the plot for the soil with the highest dose of KKM. The lowest wicking rate was observed for soil samples modified with the highest content of KKM compost The opposite effect of KKM addition was found for water. The determined values of the contact angle ranged from 8 to 24° and were the lowest for the check sample and the highest - for the sample containing 50 weight percent of KKM. Similar changes were observed in the case of apolar component of the surface free energy, y_i^LW, which ranged from 39 to 45 mJ/m². The behaviour of all analysed wettability characteristics, i.e. an increase o f the total surface free energies and the contributions arising from dispersion forces, changes in the values of contact angles and in the values of the work of spreading (and lowering the electron-donor contribution to the work of spreading, in particular) indicated that the addition of KKM increased hydrophobic character o f the investigated samples.