In this work, reduced graphene oxide coated zinc oxide flower (ZnO–RGO) nanocomposite has been prepared via a simple one-pot hydrothermal synthesis method. The morphology and properties of the proposed ZnO–RGO were characterized using SEM, Raman and UV–VIS spectroscopy. Then, an ascorbic acid (AA) electrochemical sensor was prepared based on a glassy carbon electrode (GCE) modified with the ZnO–RGO nanocomposite. An advanced performance was recorded on the ZnO–RGO/GCE compared with that of the bare GCE, ZnO/GCE, and RGO/GCE. The proposed electrochemical sensor exh...