The invention discloses a bacillus cereus BCCY22, the preservation number of which is CGMCC No. 16672, and further discloses a culture method of the strain, a formed microbial inoculum, a preparationmethod of the microbial inoculum and an application of the microbial inoculum. The bacillus cereus colony is milky white, approximately circular and slightly long, has uneven edges, uniform and opaquetexture, and the bacillus cereus BCCY22 is rod-shaped, has the length of 2.86-4.44um and the width of 0.80um-1.21um, and is in chain arrangement or exists independently; the bacillus cereus BCCY22 produce spore, wherein the spore is generated in the middle and is ellipse; cysts do not expand, and Gram staining reaction is positive; the bacillus cereus can utilize glucose and sucrose, and cannot utilize lactose. The bacillus cereus is a broad-spectrum nematode antagonistic strain, and the prepared microbial inoculum has high-efficiency prevention and treatment effects on plant nematode diseases, has certain effects of promoting crop growth and increasing yield, and is favorable for protecting environment.