The aim of the study was to determine the effect of honeybee wax impregnation on the antifungal, larvicidal, water uptake, color, and mechanical properties of wood. Wood samples (poplar, Scots pine, beech, and lime) were impregnated with melted honeybee wax under vacuum. The wax-impregnated samples were exposed to the wood-decay fungi Trametes versicolor and Neolentinus lepideus for 8 weeks. The larvicidal effect of the beeswax was tested against European old house borer (Hylotrupes bajulus L.). Water uptake, color measurements, and surface hardness were also tested. According to the obtained findings, a 34.6% mass loss was seen in the poplar control wood, and only 3.9% mass loss was found in the 100% beeswax-impregnated samples. The results showed that H. bajulus larvae could digest honeybee wax with wood when beeswax surface treatment was applied. Additionally, an average of 30% larvae mortality rate was achieved on beeswax-treated wood surfaces, compared to a 2.5% rate on the controls. However, when wood was deeply treated with beeswax, larval mortality reached 100%. In the water uptake test, beeswax-treated samples showed water repellent efficiency. The lowest water uptake (24.2%) was obtained in poplar wood treated with 100% beeswax, compared to 92.6% in the poplar control in 96 h immersion time. With the beeswax treatment, a* and b* color values increased, while the L* values decreased.