The invention discloses a dangling type micro-impulse testing device and method. A dangling system is fixed in a vacuum box, a thruster ignition power source, a circuit switch, a wire and a miniature thruster are integrated to the dangling system in a modularization mode, a dangling type micro-impulse testing system works in a vacuum environment, a remote control switch serves as a circuit switch to conduct remote control ignition, and influences of a miniature thruster ignition resistance wire power source and the wire on testing results are eliminated. A laser Doppler measurer is installed outside the vacuum box, a light path of a single beam laser head in the laser Doppler measurer is adjusted to be centered with a target reflector, the deviation of outgoing beams and incident beams is eliminated, displacement changes of the thruster are accurately measured, and influences of air friction during dangling are avoided. By means of the dangling type micro-impulse testing device and method, the working force of a miniature rocket motor in a short time can be tested, the micro impulses can be tested, and the impulse testing accuracy is high.