The invention discloses a preparation method of a bacterial fertilizer or a bacterial product. The preparation method is characterized by comprising the following steps: uniformly mixing a type A microbial agent and a type B microbial agent in the ratio of 1 to (0.1 to 10); adding the uniformly-mixed microbial agent into a pesticide residue culture medium to obtain the bacterial fertilizer or thebacterial product. Active components of the microbial agent consist of rhizobium japonicum, bacillus megaterium, bacillus cereus, bacillus subtilis, bacillus mucilaginosus, lactobacillus buchneri, bacillus amyloliquefaciens, paenibacillus polymyxa, bacillus pumillus, bacillus licheniformis, trichoderma harzianum, etc. The microbial agent and pesticide residues are mixed uniformly to obtain the bacterial fertilizer or the bacterial product. The bacterial fertilizer or the bacterial product can be applied to the facilitation of crop growth or the improvement of crop yield or the improvement of planting soil, as well as the improvement of crop disease resistance. The product can be combined with different bacterial fertilizer carriers to form a solid bacterial fertilizer, a dry or gel starchbacterial fertilizer, a liquid bacterial fertilizer, a pesticide residue waste bacterial fertilizer, a grass charcoal bacterial fertilizer, a peat bacterial fertilizer, a hibernated bacterial fertilizer, as well as a pig, cattle, sheep and chicken manure excrement bacterial fertilizer, and to form seed coatings.