This research focused on observing and measuring the 3D shape for nano-scale thin film buckling of 150nm Ti-film material deposited on organic glass substrates. With the aid of an optical microscope (2000×), the particular approaches were designed using optical wedge stepped in horizontal displacement approach and micro mechanical vertical displacement approach. The 3D shape measurement of thin film buckling on nano-scale level was carried out based on focusing-evaluation-function theory, gaussian interpolation and other theories related to digital image. After comparing the different measuring results and data from different focusing evaluation functions, an error analysis was established on the nature of such functions. In this experiment, we only focused on the measurement on the 3D shape for 150nm-thick thin film buckling. This research makes promotion in measurement on 3D shape of thin film buckling on nano-scale level.© (2008) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.