In the field of nanotechnology, Atomic Force Microscope (AFM) which is based on the interactions between an extremely sharp probe tip and specimen, has been widely utilized. In the AFM and AFM-based applications, the probe tip wear problem should be carefully considered. In this work, the wear characteristics of silicon, silicon nitride, and diamond coated probe tip under light loads were investigated. In order to identify the structure of the AFM probe tips as well as the nature of wear, High-Resolution Transmission Electron Microscope (HRTEM) and Field Emission Scanning Electron Microscope (FESEM) analyses were utilized. Using the Archard's wear equation, the degree of the probe tip wear was quantitatively assessed. Based on the experimental results and analysis, the plausible wear mechanisms of the AFM probe tips were proposed in an effort to understand the nano-scale wear.