Abstract: Recently, gas sensors based on the semiconducting metal-oxides such as ZnO have been found to be very useful for detecting ethanol vapor. Pure ZnO films have been investigated as sensors for ethanol. One of the requirements of the gas sensors is low power consumption, because the sensors need to work reliably and continuously. A low resistance material has lower driving power when it is used as a sensor. A significant resistance change can be obtained in the sensor, which results in a higher sensitivity. Several techniques have been used to prepare ZnO films, such as RF magnetron sputtering, chemical vapor deposition, sol-gel, and spray pyrolysis. In this study, ZnO film sensors deposited by dip coating method using copper as the electrode are reported. X-ray diffraction (XRD), scanning electron microscopy (SEM), and Atomic microscopy were used to characterize the structural properties of ZnO gas-sensing films that were deposited on Aal 2 O 3 substrate. Zinc oxide nano particles have been paid more attention for their unique properties. Zinc oxide has been studied in many areas such as catalysts, optoelectronics and photochemistry in order to utilize its semiconductor characteristics. Zinc oxide can be used for gas sensing material, solar cell material, display screen, photocell electrode, and UV-light emitting diodes. Gas sensors pay more attention in these days.