The invention discloses a modular gas generating device for multi-target optimization. The modular gas generating device for multi-target optimization comprises an injector, a turbulent flow section,a cylindrical section, a bent pipe section and a throat section; the injector, the turbulent flow section, the cylindrical section, the bent pipe section and the throat section are connected in seriesthrough bolts so as to facilitate detachment and replacement; and the turbulent flow section, the cylindrical section and the bent pipe section are accepted or rejected by combining the requirementson working pressure, flow and outlet temperature uniformity of the gas generating device and a testing situation of a test. According to the modular gas generating device for multi-target optimization, a plurality of design parameters can be examined through one test, so that the test number is reduced, the cost is reduced, and the test period is shortened.