The invention discloses a variable-range thrust measuring device applicable to a microminiature thruster, which comprises a working base plate, a fixed vertical beam, a movable vertical beam, pivot sleeve assemblies, a knife edge frame, a movable cross beam, a displacement measurement device, a voice coil calibration device and a damping device, and is characterized in that the working base plate is leveled through four bolts; the fixed vertical beam is installed on the working base plate and provided with overload protection bolts; each pivot sleeve assembly is composed of four pivot sleeves and two pivots, and two ends of each pivot are installed by the pivot sleeves respectively in a locking mode. The whole measuring device is equipped with five pivot sleeve assemblies which are consistent in external mechanical interface, thereby enabling the thrust measuring ranges to be 0-100muN, 0-500muN, 0-1mN, 0-50mN and 0-100mN respectively, and achieving a purpose of high-precision thrust measurement with the range being variable. According to the invention, a displacement sensor is adopted to realize displacement measurement for the cross beam, a voice coil and a permanent magnet are adopted to realize system calibration, and a copper piece and a permanent magnet are adopted to realize passive damping for movement of the cross beam. The whole set of device can operate in a vacuum simulation environment.