We present the first fiber Bragg gratings (FBGs) inscription in ZEONEX-480R microstructured polymer optical fiber (POF) by employing the fourth harmonic (266 nm) of a Nd:YAG laser system. The gratings were produced in the L-band region by the phase mask method, in 270-mu m diameter POF samples connectorized with ferrule connectors (FCs). The results of three produced gratings are reported, showing good stabilit...