Starch, cellulose, proteins, carbohydrates, lignin, tannins, beta-sitosterol, scopoletine and flavonoids were detected in the plant material of Caucalis platycarpos L. using histochemical reactions and thin-layer chromatography. The dry decoction of the plant contained polysaccharides, seven amino acids and three flavonoid glycosides. The predominant flavonoid was luteolin-7-glucoside.