The aim of this study was to investigate the impact of the bleaching and varnishing process on the collapse time in combustion of wood material. For this purpose, samples prepared from wood of European oak (Quercus petraea Liebl.) according to ASTM D 358, were covered with waterborne (Sb), synthetic (Sn), polyurethane (Pu) and acrylic varnishes (Av) in accordance with ASTM D 3023 after bleaching with 18 % solution of Sodium hydroxide (NaOH), Hydrogen peroxide (H2O2), Calcium hydroxide (Ca(OH)(2)), Sodium silicate (NaSiO3), acetic acid (CH3COOH), sodium disulfide (Na2S2O5), oxalic acid (H2C2O4) and potassium permanganate (KMnO4). The collapse time on combustion of prepared samples were determined according to ASTM E 160-50. According to the result of reseach, collapse time according to varnish types was obtained the highest time acrylic (1129 sn), the lowest time synthetic (651.1 sn), according to bleacher types was gained the highest time R-3 (1114 sn), the lowest time R-2 (438 sn). According to interaction of bleaching and varnish types was obtained the highest time Sb+R-5 (1460 sn), the lowest time Sn+R-3 (840 sn). Accordingly, this situation can be taken into consideration in areas where burning is expected to be late.