A review is presented of the recent state of the problem of soil algae productivity in terrestrial ecosystems on the basis of literature data and our own research. It is shown that the organic matter accumulated by soil algae is highly mobile. The following parameters were analyzed: the biological production, the time of the biomass turnover, and the rate of the algal organic matter renewal in the soil. The average monthly production of algae ranged from 0.9 to 765 g/m2, the rate of the organic matter renewal ranged from 0.03 to 25.5 g/m2 per day, and the time of the algal biomass renewal ranged from 0.1 to 7 days.