Sycamore (Acer pseudoplatanus L.) seeds are frequently used in forest nurseries and therefore the knowledge of their proper treatment is desirable. Seed stratification recommended by the Czech standard is two months but there are not many studies which review the appropriate length in Central European conditions. The paper evaluates the influence of seed stratification length on their germination capacity. The seed samples were treated in different ways to evaluate their reaction to these different handling conditions. The data proved a significant increase of germination after 42 days of stratification. The data also suggests that the better stratification medium is a substrate than wet filter paper.