The thesis deals with natural aging of beech, oak and spruce samples treated with Aquawood TIG HighRes Weiss and Aquawood Spritzlack X or 3-layer Aquawood TIG HightRes Weiss, Aquawood Intercare SH and Aquawood Spritzlack XT. The samples were exposed to the exterior on June 21, 2018, in exposure stands at 45º with a south-west orientation. During the exposure time of 0 to 300 days, color change, gloss change and paint defects were monitored. During aging, the brightness of the coating was reduced (*L * −5), to a minimum decrease of the green tint (∆a * + 0.3) and an increase in the yellow tint (∆b * +1.5). The overall color difference has changed in the aging process (ΔE + 4), which in general is considered a significant color change from a visual assessment point of view. Microscopic analysis revealed clogging of the surface with microscopic particles deposited on the surface of the paints. Depending on the time of aging, the coatings become dull. During the natural aging process, the samples treated with the 3-layer coating system appeared to be stable without defect formation. During the exposure of the samples with the 2-layer coating system, defects gradually appeared, namely the leakage of resin, the formation of blisters and the formation of cracks on the surface of the coatings.