The invention discloses a Bacillus amyloliquefaciens preparation for controlling viral diseases of plants, and the preparation provided by the invention contains the following ingredients: a Bacillus amyloliquefaciens culture liquid and diatomite, wherein the viable count of Bacillus amyloliquefaciens in the Bacillus amyloliquefaciens culture liquid is 100 billion cfu/mL; the weight of the diatomite accounts for 8% of the total weight of the preparation; and the strain, named as Bacillus amyloliquefaciens, is preserved in the China general microbiological culture collection center (CGMCC) on April 23th, 2010, and the collection number is CGMCC No.4127. The Bacillus amyloliquefaciens preparation for controlling the viral diseases of plants has the capabilities of inactivating virus particles, inhibiting reproduction and proliferation of viruses and inducing host resistance; and the control efficiency is more than 80% in a green house and 49.09% in the field. The Bacillus amyloliquefaciens preparation has high application values for controlling viral diseases of crops (especially tobacco crops).