Field trials were carried out in 2009-2010 in organic farms located in Podlasie region and in conventional farms located in wielkopolskie and dolnoslaskie districts. The objective was to evaluate the effect of applied agronomic procedure on growth, development and yields of Bukoz cultivar of oil flax. The yield and its structure as well as seed quality (1000 seed weight, germination capacity, fat content, composition of fatty acids and content of heavy metals: Cd, Cu and Zn) were investigated. The oil flax cultivar Bukoz in organic farms gave yields on the level 30,4-37,0% lower as compared to yields obtained in conventional farming. This was a result of lower (as compared to conventional farms) plant density at harvest, despite higher 1000 seed weight. Analysis of chemical composition of seeds showed higher content of fat in seeds harvested in organic farms. Additionally, yields from organic farms showed higher content of linolenic and oleic fatty acids. Seeds from conventional farms had higher content of linoleic fatty acid.