Substances that could play a role in maintaining seed viability (phenolic compounds, α-tocopherol, sterols, ascorbic acid, glutathione and soluble proteins) were estimated in beech (Fagus sylvatica L.) seed lots that had been stored for 2, 5, 7 and 10 years at − 10°C. Germination capacity was strongly and positively correlated with amounts of total phenolic compounds, ultraviolet (UV)-absorbing phenols and soluble proteins. Moderately strong relationships appeared between germination capacity and α-tocopherol and ascorbic acid contents. Total sterol and glutathione contents were not correlated with germination capacity. A strong, negative correlation was found between germination capacity and reactive oxygen species (ROS), such as superoxide radical () and hydrogen peroxide (H2O2), as well as with lipid hydroxyperoxides (LHPOs). The putative role of these compounds in the maintenance of beech seed viability during long-term storage is discussed.