A microfield experiment was conducted on a good rye soil complex to study influence of synthetic growth regulator - Stymulen 60 SL (active substance - 4,4-dimethylmorpholinic chloride) on yield, yield structure components and some quality features of buckwheat seeds. Stymulen 60 SL acted profitably and distinctly on the buckwheat seeds yield and on dry matter of buckwheat stems. No significant differences were found in other investigated yield structure components as well as crude protein and macro elements concentration in buckwheat seeds.