The invention discloses a multifunctional 
microorganism soil repairing agent as well as preparation and application thereof and belongs to the fields of biological techniques and environment protection. The multifunctional 
microorganism soil repairing agent is made of the following raw materials in parts by weight through uniform mixing: 30-60 parts of nano 
chitosan, 10-20 parts of 
humic acid, 10-20 parts of nano 
charcoal and 20-30 parts of a composite 
microbial agent, wherein the composite 
microbial agent is prepared from fresh 
benzene bacillus, B.sonorensis, lysinibacillus sphaericus, 
bacillus licheniformis, 
bacillus circulans, bBacillus thuringiensis, 
achromobacter denitrificans, saccharothrix australiensis, 
Rhodococcus zopfii, pseudonocardia sulfidoxydans and pseudonocardia dioxanivorans through purification, optimization, 
fermentation and 
drying dehydration. The multifunctional 
microorganism soil repairing agent disclosed by the invention is capable of replacing conventional physical and chemical repairing techniques, is capable of degrading complex pollutants, is wide in repairing range, is capable of preventing soil degradation and inhibiting diseases and insects in environments, and has the advantages of being good in repairing 
treatment effect, low in cost and economic and environment-friendly.