The results of an experiment on the use of a Labforce 5 Lux – LED flat panel bioreactor (Infors HT, Switzerland) for the cultivation of Tisochrysis lutea (Haptophyta) are presented. During the three-week experiment, the number of cells, their size, the content of chlorophyll a and carotenoids, neutral lipids were evaluated. It was shown that the maximum number of cells was fixed by the end of the experiment – at 21 days. An increase in the proportion of cells with a size of 4-6 μm was recorded on the 11th day of the experiment. The greatest accumulation of carotenoids occurs on day 18, and neutral lipids on 14th–21st of the experiment.