We have studied the mechanical properties of particleboards with different proportions of bark. Splinter wood was from spruce wood, fir and pine trees, splinter bark was from larch, spruce, pine and stone pine trees. We prepared 5 types of splinter wood boards with bark proportions of 0, 10, 20, 40 and 50 %. We cut out the testing samples from the splinter wood boards, and measured the moisture content, thickness, density, thickness swelling after deluge into the water, layered and bending strength and modulus of elasticity. We also performed separate sowing analysis for splinter wood of timber and splinter wood of bark. It was found out that the proportion of greater splinter wood was greater in the wood, and with smaller fractions the proportion of splinter wood was greater in bark. In measuring the humidity, it was found out that there were minimal differences in the humidity. Measuring the thickness of splinter wood boards showed that by increasing the proportion of bark, the thickness of splinter wood boards was decreasing, and the density increasing. The measurement of thickness swelling, after samples being sunk into water, revealed that by increasing the proportion of bark the thickness swelling was decreasing. Measuring the bending and layer strength showed that the splinter wood board with a 10 % share of bark had the maximum values, however, a board without bark had the maximum value of modulus of elasticity, and by increasing the proportion of bark it was decreasing.