The aim of this article is to characterize the seed industry in Poland and assessment of changes in supply, demand and prices on the market of classified seed of cereals in Poland. The discussion relates to the main groups of participants making up the breeding and seed industry, i.e. the breeding, seed, as well as breeding and seed entities. The characteristics of entities from the breeding and seed industry’s environment has also been presented. The article presents the analyses of the cereal seed market in Poland between the years 2008-2012, including the changes in supply, demand and market prices. The analyses indicated an increase in sales of the certified seeds in Poland by 25.3%. Winter wheat was the dominant seed in terms of trade structure throughout the entire period. The increase in sales of classified seeds in the cereal segment took place in conditions of significant seed prices’ increase in the studied period.