Multi-walled carbon nanotubes (MWCNTs) onto flower-like patterned ZnO seed layers were prepared by spin coating method. The etching of the MWCNTs was examined by HCl acid treatment. The effect of structural, morphological and elemental properties of the ZnO/MWCNTs were determined by XRD, SEM, and EDX, respectively. The gas sensing properties of ZnO seed layer and MWCNT/ZnO nanocomposites were studied as a function of operating temperature and gas concentration. The incorporation of MWCNT were given results such as reducing the operating temperature to 70 degrees C and enhancement in sensor response for 25ppm CO gas. It was obtained that the highest sensing response of 62% at 70 degrees C for raw-MWCNTs/ZnO sensor as compared to etched-MWCNT/ZnO and ZnO sensor which gave a sensing response of 19% and 21% at operating temperature of 70 degrees C and 150 degrees C, respectively. Results showed that the deposition of metal oxide sensors with MWCNT is a promising strategy for improvement of CO gas sensing properties.