The use of Atonik, a synthetic biostimulant, to improve the yield and quality of red and white bean was studied. The 0.1% and 0.3% solutions of Atonik biostimulant were applied by a single and double spraying of plants. The yield of the investigated common beans increased after Atonik treatment with the highest impact recorded upon the double spraying with the 0.3% solution. The studied treatments had no significant effect on phenolics content; however, some differences were found in the antioxidant potential. The applied biostimulant had no significant effect on the reducing power either. The angiotensin-converting enzyme inhibitory activity was noted only for Aura bean; however it remained unchanged upon the biostimulant treatment. All the analyzed types of application had no significant effect on starch and protein contents; however, a slight, insignificant decrease was observed in starch content in Aura cultivar. An insignificant decrease of globulins in beans obtained from plants double-sprayed with 0.1% Atonik should also be noted. Most importantly, the studied treatment did not enhance the activity of α-amylase and trypsin inhibitors. In summary, results of the study demonstrate that Atonik effectively improves the yield and nutraceutical potential of beans without any negative effects on their nutritional quality.