Nanostructured Zinc Oxide (ZnO) have a significant interest in electrochemical sensor applications. This paper presents the design and fabrication of ZnO nanorods (NRs) based electrochemical capacitive sensor for pH measurement applications. Two-step programmed spin coating deposition of ZnO seed layer followed by the hydrothermal growth of ZnO nanostructures having NRs morphology lead to the fabrication and calibration of the capacitive sensor. The structural and chemical composition of the ZnO thin film layers is examined with field emission scanning electron microscopy (FeSEM) with energy dispersive spectrometer (EDS) and X-Ray diffraction (XRD) studies. The synthesized NRs exhibit crystallinity properties and average crystallite size of the ZnO NRs is 54.18 nm. The ZnO NRs developed on Aluminum substrate was used as a capacitive sensor and it has a potential application in pH measurement in a micro solutions media.