Parameters of surface roughness, contact angle and surface free energy (SFE) on Al2O3 as a material wich is used as the non-image areas for the offset tehnique has been determined depending on the concetration of the developing solution. Different concentration of NaOH water solution has been used as the developing solution, and diiodomethane, glycerol and water were used as standars for measuring the contact angle and surface free energy. NaOH solution has caused the dissolution of Al2O3 surfaces during the developing process. By dissolution of Al2O3 peaks of the nonprinting elements the platous has been formed and could be dectected by measuring the surface roughness parameters. Decreasing of Rp and Rv values have indicated the changes in surface roughness. The anode layer had lower vaues of roughness which caused the reducing of the number of acticve points for the adsorption of fountain solution. Depending on the used standard, contact angle values on the non-image areas initially have been decreased with increasing of development time, but with certain increase in later stages. Longer development in all concentrations of NaOH has caused a slight increasing of SFE in the first stages with certain decrease in the later stages. The disperse components of SFE on all observed samples of plates has been unchanged regardless of the developing duration. Similar results have been detected with the polar components where the values have been increased in the first stage followed by decreasing in the other stages.