This application relates to the field of microbial fermentation, more specifically, it relates to a multi-bacteria fusion symbiotic fermentation process for disease resistance and growth promotion, including the following steps: Step (1), preparing bacterial liquid: preparing Paenibacillus polymyxa respectively liquid, yeast liquid, Streptococcus thermophilus liquid; step (2), fusion symbiotic fermentation: add fermentation medium to the fermentation equipment, control the pH value and temperature of the fermentation medium, and add Paenoid polymyxa while stirring the fermentation medium Bacillus liquid, continue to stir and ferment; then control the pH value and temperature of the system, add yeast liquid while stirring, continue to stir and ferment; then control the pH value and temperature of the system, add Streptococcus thermophilus liquid while stirring, continue to stir and ferment, and produce Multi-bacteria fusion symbiotic fermentation broth. The multi-bacteria fusion symbiotic fermentation process of the present application mixes growth-promoting rhizosphere probiotics and disease-resistant rhizosphere probiotics through mixed fermentation, reducing the production cost of bacterial agents, with diverse flora, strong adaptability to the environment, and a wide range of applications .