Zinc oxide (ZnO) is very important semiconductor with wide band gap (Eg=3.37 eV) and large exciton binding energy of 60 meV at room temperature. It is very promising candidate for such devices like gas sensors[1], light emitting diodes[2], solar cells[3], lasers[4]. Doping of ZnO with group III elements is commonly employed to enhance n-type conductivity of ZnO transparent electrodes. The ZnO doping by Al generates a free electron in the conduction band. Al atoms in thermodynamic equilibrium condition substitutes Zn atoms in ZnO crystal, but concentration of Al depends on growth method: sol-gel method, hydrothermal method, atomic layer deposition. In this work, we investigated structural, optical and electrical properties of pure ZnO and Aldoped ZnO samples prepared by sol-gel method. Sol-gel process is a wet-chemical method widely used in material science and ceramic engineering. This method is used for materials fabrication starting from a colloidal solution (sol) that acts as the precursor for an integrated network (gel). In our work, precursor is zinc acetate (Zn(CH3COO)2). For surface topography studying we used atomic field microscope (AFM). We also measured ZnO and ZnO:Al photoluminescence (PL) spectra before and after irradiation by Nd:YAG laser fourth harmonic (λ=266nm, I~15MW/cm2, τ=15ns). 4-point probes method to measure samples surface resistivity was used. After the laser radiation two orders decrease of resistivity was observed, which is very important for transparent electrodes. PL measurements showed changes of optical properties in irradiated ZnO:Al sample. Moreover, from AFM measurements we obtained that grain size increase twice. Explanation of obtained results will be proposed.