Abstract: By using Nostoc sphaeroides Kuetzing as material,we studied its mass cultivation indoors,the structure and biochemical composition of the colony in this paper.During 15 months of cultivation,the biomass productivity was 38.3～293.7 kg(FW)every month,and in the volume of one cubic meter,the biomass productivity was 9.58～77.45 kg(FW)every month,and it was evidently decreased by the high temperature.The cross section of colony in N.sphaeroides showed that there was obvious difference lied in the exterior and interior structure of the colony with the diameter of 10 mm.The obvious differences also existed in the length and array of trichomes.At the same time,we measured and analysed cultivated N.sphaeroides’s biochemical composition.The results show the following: in cultivated N.sphaeroides,the protein content was 29.69%,including 16 kinds of amino acid.Compared to wild N.sphaeroides,the fatty acid content was far lower,only 0.78%.The vitamin content was lower.According to national standard to food sanitation,the heavy metals content,including arsenic,plumbum,hydrargyrum,cadmium,were very low.