In this paper, a method to characterize the volatile compounds in Chinese liquors by comprehensive two-dimensional gas chromatography/time-of-flight mass spectrometry has been developed. The selection of column combination and the optimization of temperature program are discussed. With the optimized conditions, ordered chromatograms are achieved in the two-dimensional plane, which is useful for the identification of unknown compounds. According to the automated data processing by TOFMS software, combining with the ordered chromatogram and the retention index database developed by our group, a total of 528 components are identified in a Moutai liquor sample, including organic acids, alcohols, esters, ketones, aldehydes, acetals, lactones, nitrogen-containing and sulfur-containing compounds, etc. In addition, the contribution of some important aroma compounds to flavor of Moutai liquor has also been studied.