The ultra-violet detector using zinc-oxide nanorods was fabricated and its performance is measured and evaluated. Zinc-oxide nanorods which are synthesized on Fluorine doped Tin Oxide (FTO) glass by hydrothermal method under various conditions. An electrode is formed using silver ink, it is made easy to measure using a copper tape. As a result, the sample which is synthesized with 250 mM seed of methanol base in polyethylenimine (PEI) free precursor solution has the excellent reaction / recovery rate. In this paper, when zinc-oxide nanorods are used in the ultra-violet detector, it can be confirmed which condition has the most optimal performance.