Using nanoindentation technology combined with finite element simulation and dimensional analysis，the parameters of the power-law constitutive model for single-crystal germanium were inverted.Nanoindentation tests were conducted on the（111）crystal plane of single-crystal germanium to obtain load-displacement data.A dimensionless functional relationship corresponding to the experiments was established based on finite element simulation，and the specific parameters of the power-law constitutive model were determined through fitting.The experimentally obtained load-displacement curves exhibited high consistency with finite element simulation results， validating the reliability of the inversion process.The results indicate that the power-law constitutive model obtained through this method effectively describes the elastic-plastic mechanical behavior of single-crystal germanium during nanoindentation.And it provides a reliable basis for mechanical modeling of such type of material at the micro-nano scale.