In the study of shallow Lake Solenoye located on the territory of Omsk mass vegetation of cyano-bacteria of the species Arthrospira fusiformis (ar-throspira, spirulina) was found. Previous analysis of arthrospira phytomass showed its high nutritious value - the protein content in it in different years was 32.8-46.06 %. In this regard the researches were carried out to study the effect of arthrospira phytomass on the organism of experimental ani-mals. The selection of biomaterial was carried out with Apstein plankton network in the period from 05.09.2016 to 11.09.2016. After spinning crude phytomass was placed in plastic bags and subject-ed to freezing in a freezer at -18 ° C. The rats of the first test group in addition to the diet received arthrospira phytomass in a dose of 1.0 g/kg of body weight once a day for a month. By similar regimen the animals of the second test group received ar-throspira in a dose of 2.0 g/kg of body weight. Dur-ing the experiment the animals were under obser-vation, the death of rats was not recorded, moreo-ver the animals of all groups were active, they ate well, and the rats of experimental groups actively consumed arthrospira phytomass. The results of histological studies of liver and kidney tissues sug-gest that adding Arthrospira fusiformis in rats’ diet at a dose of 1.0 and 2.0 g/kg of body weight for a month does not cause any morphological changes in the liver and kidneys, on the contrary, the pro-cesses of stimulation of reparative histogenesis are observed, which can serve as a basis for recom-mending it as an additive for the cell restoration in a damaged organ.