The invention provides a micro force measuring device, belongs to the technical field of micro force value calibration and measurement testing, and aims to solve the problems that the structure is complex, the action line of the force cannot be fixed easily, and the cost is high in the prior art. The micro force measuring device comprises an unequal arm balance, a force value replication device, a micro-displacement measuring device and a computer control system, wherein a tray is arranged at a long arm end part of the unequal arm balance; an edge cutter structure is arranged at a short arm end part; the edge cutter structure is connected with the micro-displacement measuring device through the force value replication device; the output end of the micro-displacement measuring device is connected with an insulating rod through a connecting sleeve; and the insulating rod is connected with a threaded hole in an upper end cover of an inner electrode of the force value replication device. According to the micro force measuring device, the force value replication device is used for replicating a micro force value, relative micro displacement of the inner electrode is measured through an improved digital display micrometer, the force value change is changed into the precision capacitance gradient change of an electricity quantity relative to the displacement, balance is formed through a lever structure and a standard weight dead weight force, the structure is simple, and the cost is lower.