A development of the technique that enables the simple, rapid, and damage‐free sample preparation for cross‐sectional transmission electron microscopy (X‐TEM) analyses is quite important. Here, we propose a silicon (Si) oxide nanofiber (SON) formed on a tip of an atomic force microscope cantilever as a substrate onto which materials in question are deposited for X‐TEM analyses. Based on the technique for the ion‐irradiation–induced carbon nanofiber (CNF) fabrication onto atomic force microscope cantilever tips, Si‐included CNFs (Si‐CNFs) were fabricated onto cantilever tips. The prepared Si‐CNFs were then annealed at 1000°C in atmospheric ambient to form SON‐tipped cantilevers. Si oxide nanofiber, consisting of mostly Si and O, was linear in shape and was amorphous in crystalline structure. The high performance of the SON‐tipped cantilever was demonstrated for the X‐TEM analyses of ZnO films deposited thereon by an arc plasma deposition method, suggesting that it is promising as a substrate for X‐TEM analyses.