The invention provides a control system of a fire extinguishing vehicle. The control system comprises an analysis module, an error term calculation module, a proportional term calculation module, a differential term calculation module, an integral term calculation module and an inner ring calculation module. Through cooperation of a main control board and a chassis inertial navigation unit, a chassis motor, a heading angle control motor and a pitch angle control motor are subjected to closed-loop control so as to ensure that the course can be adjusted adaptively, and the deviation in the advancing process of the fire extinguishing vehicle is corrected automatically. Therefore, the control precision of the fire extinguishing vehicle is higher, and operation is more convenient.