Abstract: A dwarf mutant with abundant sucker was observed in populations of second generation of Nicotiana tabacum (L) cv.GT11 which experienced space mutation in a recoverable satellite, the Chinese third unmanned spacecraft “Shen-Zhou III”, and these heredities were stable. It was named as T-srd, Tobacco of Sucker-rich and Dwarf mutant. The suckers of T-srd emerged at the first leaf node in 5 weeks after sowing. In field, the emergence of sucker was orderly from bottom to top, and under the control of the apical bud, which had no sucker until the node laid under half of the stalk height at first flower stage. At 90 days after transplanting, the plant height, length of internodes, and stem girth of T-srd were lower than those of GT11. There was no sucker-rich and dwarf phenotype in F1 population, and the segregation ratio in F2 population of seedling between sucker-rich and sucker-free phenotype in Chi-square test followed the Mendel Genetic Law. Those results suggest that the sucker-rich and dwarf trait is a qualitative character which belongs to recessive mutation controlled by single gene.