At a time when organic farming methods are gaining popularity, buckwheat cultivation is becoming more and more important, because it is in the biological system that the positive contribution of this species to the crop rotation is most effectively seen. The biochemical composition of buckwheat is of high dietary value, however, it may be different for different varieties under the same growing conditions, and the yield, economic characteristics and ripening time also depend on the genetic characteristics of the varieties. The aim of the study was to evaluate the productivity and chemical composition of buckwheat cultivars 'Aiva', 'Noja' and 'Lileja' and their suitability for the production of extruded products. The research data show that the most suitable varieties for food production in Latvia are 'Aiva' and 'Nojas', which provide a higher yield and are 10-14 days earlier. The high protein content (13.45-17.12%), the low fat content (2.51-2.82%) and the fiber supply show that all three varieties are high-quality raw materials for the production of both gluten-free and other products. The content of protein, amino acids, fat, starch and trace elements does not differ between buckwheat varieties grown under the same conditions.