Odor pollution has become a major environmental problem in municipal solid waste composting. The odor samples at different composting phases of kitchen waste were collected and analyzed by olfactometry and gas chromatography-mass spectrometry (GC-MS). The correlation between the odor concentration and the emission of odor compounds was also analyzed. The results showed that there were 43 kinds of volatile organic compounds (VOCs) in the composting process of kitchen waste, including 5 kinds of sulfur odor compounds, 22 kinds of hydrocarbon compounds, 11 kinds of aromatic compounds and 5 kinds of other odor compounds. The correlation analysis indicated that the odor concentration was very significantly correlated with the emission of hydrogen sulfide, methanethiol, 1,3-xylene and o-xylene (P < 0.01), and significantly correlated with the emission of dimethyl disulfide and p-xylene (P < 0.05). Therefore, those 6 kinds of odor compounds should be intensively monitored and controlled during the composting process of kitchen waste.