Fuente: WIPO "tomato" The present disclosure provides a strain of Bacillus velezensis and its use. The strain of Bacillus velezensis BJ-1 disclosed herein has a depository number CGMCC No. 24113. This strain exhibits antibacterial activity against plant pathogenic fungi and possesses broad-spectrum antibacterial effect. The result of in vitro leaf inoculation detection showed that the fermentation liquid derived from Bacillus velezensis BJ-1 exhibited significant prevention and control effects on tomato gray mold. The relative prevention and control effects of 1×107 CFU/mL the fermentation liquid on tomato gray mold were determined to be 68.95% and 88.28%, respectively. The result of the field trial demonstrated that Bacillus velezensis BJ-1 water-dispersible powder exhibited significant prevention and control effects on tomato gray mold. The relative prevention and control effects of 2.0×1010 CFU/g (450 g/mu) Bacillus velezensis water-dispersible powder were determined to be 80.48%. The strain of Bacillus velezensis disclosed herein has potential for biocontrol, including the manufacturing biocontrol agents and microbial fertilizers for plant pathogenic fungi.