The utility model discloses a special pump of bus fire extinguishing systems, include motor and multistage pump, the motor is 24 volt direct current motor, is equipped with the impeller in the multistage pump, and motor drive impeller, multistage pump include feed liquor section and play liquid section, and the feed liquor section is located the one side of keeping away from the multistage pump respectively and is located the one side near the multistage pump with play liquid section, and the terminal surface of feed liquor section is equipped with side along the radial liquid outlet that is equipped with of inlet, play liquid section along the axial setting. The utility model discloses simplify the structure, reduce the cost, the noise reduction, the even running, increased flow improves the lift, strengthens fire extinguishing systems's rescue efficiency.