The peculiarities of the growth of spirulina (Arthrospira platensis (Nordst.) in water from highly mineralized lakes of the forest-steppe and steppe zones of the Southern Trans-Urals are investigated. The highest growth rates were established within the mineralization range of 3-30 g/l. The maximum mineralization values for spirulina growth were 80 g/l. pH values did not affect the intensity of spirulina growth. The longest duration of spirulina cultivation in lake water without the addition of nutrient medium was 3 months. With the addition of spirulina, the number of artemia in the water from the lake increased by one order of magnitude.