The invention discloses a high-density fermentation method of recombinant bovine granulocyte colony-stimulating factor engineering bacteria. The method comprises the following steps: performing freeze-drying preservation of the recombinant bovine granulocyte colony-stimulating factor engineering bacteria; performing activation, shake-flask culture and seed culture; then transferring the recombinant bovine granulocyte colony-stimulating factor engineering bacteria into a fermentation tank, ventilating, stirring and fermenting for culture, wherein the dissolved oxygen level is guaranteed by increasing the stirring speed and air flow in the culture process in the fermentation tank; performing high-density fermentation of the recombinant bovine granulocyte colony-stimulating factor engineering bacteria through fed-batch culture and variable index-constant pH value mixed flow feeding. Abnormal production arising from strain degeneration in the fermentation process is reduced; the fermentation, feeding culture medium and feeding method are optimized; the fermentation method provided by the invention has the advantages that the fermentation process is simple, an ideal high concentration of viable bacteria can be obtained, the stability is high and the like, and can be applied to scale production of the recombinant bovine granulocyte colony-stimulating factor engineering bacteria.