The results of investigation and identification showed that black necrosis symptom of the lower stem of flue-cured tobacco plants in Baoshan was mainly induced by the infection of Ralstonia solanacearum E. F Smith. The occurrence and prevalence of Ralstonia solanacearum E. F Smith had close relationship to tobacco variety, soil, climate and cultivation management. In this regard, some agricultural measures for integrated control of Ralstonia solanacearum E. F Smith were put forward.