The article presents the results of research aimed at evaluating the productivity of the microalgae Chlorella vulgaris Beijer., grown on modified nutrient media and supplemented with a coordination compound containing barium. It was found that increased concentrations of this compound have an inhibitory action on the Chlorella strain. A stimulatory effect was registered when the concentra tions of 50, 10, 5 and 1 mg/L of the tested coordination compound were administered, where the biomass obtained was higher by 6.8, 24.54, 13.06 and 0.90% in relation to the witness.