In this study, attempts have been made to estimate the representative stress-strain relation of metallic materials from indentation tests using an iterative method. Finite element analysis was performed to validate the method. The results showed that representative stress-strain relations of metallic materials using the present method were in a good agreement with those from tensile tests. Further, this method was extended to predict representative stress-strain relation of ultra-thin molybdenum films with a thickness of 485. nm using nanoindentation. Yielding strength and strain hardening exponent of the films were therefore obtained, which showed a good agreement with the published data.