Three kinds of archaeological wood unearthed from different sites were selected as test samples, and erythritol was used as the dimensional stabilizing material. The test samples were infiltrated with the erythritol solution with different mass fractions in a constant temperature (50℃) water bath. After infiltration, the test samples were dehydrated and dried by vacuum freezing. The dimensional conservation effect of erythritol on archaeological wood was investigated from the aspects of dimensional stability, environmental stability, mechanical properties and micro morphology. The results of the dimensional conservation test show that erythritol, as the dimensional stabilizing material, could play a good role in the dimensional conservation of archaeological wood, and that the dimensional conservation effect was promoted with the increase of the mass fraction of erythritol. The erythritol solution with a mass fraction of 30% significantly improved the dimensional stability, environmental stability and mechanical properties of archaeological wood. Erythritol precipitates on the cell wall of archaeological wood in the form of crystals, which support and strengthen the archaeological wood tissue, and thus improve its dimensional and environmental stability.