Summary: 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 concentrations of 50 mg/L, 10 mg/L, 5 mg/L 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. The inoculum was obtained from the Chlorella vulgaris culture in the middle of the exponential growth phase and separated from the borscht nutrient medium by filtration. The amount of inoculum was 0.625 g/L Fresh biomass Erlenmeyer balloons inoculated with chlorophyte Chlorella were placed on special stelae at an artificial illumination of about 4000 lx and temperature of 24oC. After 8 days of action of the coordinating compound chlorella vulgaris strain was subjected to the study. Statistical processing of the obtained data was carried out using the computer program "STATISTICA 7", the standard error of the average was also determined. The productivity of the microalgae strain was determined according to the methodology in force .