Abstract: To clarify the effects and mechanisms of silicate fertilizer on tobacco resistance against bacterial wilt disease, field experiments were carried out with sodium silicate (Na₂SiO₃) on the disease incidence, disease index and lipid membrane peroxidation of Yunyan87. The results showed that Na₂SiO₃ application reduced the disease incidence and disease index on tobacco bacterial wilt disease. Comparing with the control, the disease incidence of tobacco seedlings treated with Na₂SiO₃ on the 90th and 100th days after transplanting decreased by 13.14% and 12.08%, and the disease index by 23.34% and 21.26%. The difference between the treated tobacco and the control was statistically significant. With the proceeding and depravation of bacterial wilt disease, the contents of H₂O₂ and malondialdehyde (MDA) in tobacco leaves as well as membrane permeability and K⁺ leakage increased. Na₂SiO₃ application significantly decreased the contents of H₂O₂ and MDA, alleviated the membrane damage of tobacco, improved catalase activity, by significantly reducing the activities of superoxide dismutase and peroxidase.