One of the potential application areas of sol-gel derived coatings is high power solar radiation collectors. Such a coating should be coated onto enamelled steel tubes and should have high coefficients of absorption and low coefficients of emission of solar light. Additionally sol-gel coating has to reduce porosity of enamel surface. Various sol-gel systems were used, both single component TiO2 un SiO2 systems, as also two- and ternary TiO2 - SiO2, TiO2 - SiO2 - ZrO2 systems. Sol-gel coatings were obtained by dip-coating method. Obtained materials were investigated by the use of scanning electron, atomic force and optical microscopy, X-ray diffraction and porosity of enamel-sol-gel coating was tested by poroscope.