A method for controlling tobacco bacterial wilt and an application of NaHS in controlling the tobacco bacterial wilt are provided by the present disclosure, and the disclosure belongs to the technical field of plant disease control. By measuring the growth effect of Ralstonia solanacearum in tobacco through plate and shake bottle experiments, the disclosure finds the NaHS has an inhibiting effect on the growth of the pathogen of bacterial wilt; and the influence of different concentration of NaHS on the incidence of bacterial wilt in tobacco is detected, and the result also shows that NaHS has a good effect on resisting bacterial wilt in tobacco. The disclosure finds and proves for the first time that NaHS is an effective antibacterial substance against bacterial wilt and provides a new method for prevention and controlling of the tobacco bacterial wilt.