Metal-organic-framework(MOF)-derived pure ZnO and ZnO/Co ₃O ₄composite microstructures with different ratios are prepared by the sol-vothermal method. The crystalline structure, morphology and chemical composition for each of the prepared micro-structures are analyzed by X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray energy dispersive spectroscopy (EDS), X-ray photoelectron spectroscope (XPS), and surface area analyzer respectively. The Gas sensors based on the as-prepared materials are fabricated and their performances of sensing various gases are investigated. The measurement results show that most of the gas sensors exhibit the highest responses to cyclohexanone gas within the test temperature range, and the composite with an appropriate amount of Co ₃O ₄can obviously promote the cyclohexanoe-sensing property of ZnO microstructure. The response values of ZnO/Co ₃O ₄composite microstructures to cyclohexanone first increase and then decrease with Co ₃O ₄content increasing. The ZnO/Co ₃O ₄composite microstructure sensor with a zinc-to-obalt ratio of 1∶0.1 shows that its value of response to cyclohexanone with a volume fraction of 100 × 10 ^–6at the optimum working temperature (250 ℃) can arrive at 161, which is 6.4 times higher than that of ZnO microstructure under the same condition. Besides, its response and recovery time are 30 s and 35 s, respectively. This excellent detection performance is attributed mainly to the synergy effect between ZnO and Co ₃O ₄. The work has an important application value in the high-performance detection of cyclohexanone.