The invention discloses a measurement method for a spatial six-dimensional force, and the method is used for measuring the spatial six-dimensional force of an aircraft model, and employs a mode of combining a double-tail support and bracing wires. The method comprises the steps: considering the model to be fixed in an actual measurement process, building a mathematic model of a six-dimensional force withstood by the model in a space according to the principle of static equilibrium, measuring the component of an acting force withstood by the model through a three-directional pressure sensor installed at a tail supporting rod and a unidirectional force piezoelectric sensor connected with an upper bracing wire and a lower bracing wire, and achieving the measurement of the six-dimensional force withstood by the model through solving the built mathematic model. According to the invention, the method has the advantages in that the bracing wires are small in supporting interference and a hard-type supporting system is good in stability, and overcomes the difficulties of big vibration and instability when a narrow, long and heavy module employs a single-tail supporting mode. After the bracing wire auxiliary supporting is added, the method improves the rigidness of a testing system, reducing the pressure on the rigidness design of a tail support, and reduces the size of the tail support.