Karyotype of sturgeons Huso huso, Acipenser stellatus, and Acipenser persicus from southern region of- the Caspian Sea, has been examined by use of blood tissue culture. By counting fifty completely extended metaphase plates, the number of chromosomes in Huso huso, and Acipenser stellatus, were determined to be 2n=115±1, NF=356, and 2n=114±1, NF=372 , respectively. Obtaining sufficient number of suitable chromosome extensions tor Acipenser persicus was not passible, therefore its chromosomal number and karyotype were not determined. More research is required for this species. According to the basic estimations, It is presumed that the chromosomal number of this species is more than 2n=250. The karyotype and chromosomal number of this species have not been determined.