The nanoindentation and nanoscratch are the most representative tests of the micromechanical property testing of materials. The hardness, modulus of elasticity, adhesion and other parameters of the tested materials can be obtained by continuously recording the loaddepth relationship curve. In this paper, a nanoindentation loading device with fixed indenter and moving specimen is proposed, which is driven by piezoelectric stack and flexible hinge to realize indentation and extrusion. Firstly, two schemes of rightangle flexible hinges for nanoindentation/scratch are discussed, and the static and modal analysis are carried out. Secondly, the detailed structure design and finite element analysis of the precision loading unit are completed. Finally, a prototype of loading device is manufactured and the indentation experiments are performed. The result shows that the device can measure material hardness accurately and bears good stability.