Abstract: Analysis of volatile compounds in wheat biogas residue was conducted by headspace solid-phase microextraction combined with HS-SPME/GC-MS, and the bases of stink were also analyzed. The results showed that the best extraction condition of solid- phase microextraction was using 65 μm PDMS/DVB extraction head for 30 minutes at 60℃. A total of 49 volatile compounds were isolated and identified in the untreated wheat biogas residue, including 3 alcohols, 3 acids, 7 esters, 18 hydrocarbons, 5 ketones and 13 heterocyclic compounds. The untreated residue contains 2-phenyl-1-propene, dimethyl trisulfide, dimethyl tetrapsulfide and benzpyrole, which were the main reason for the stink. There were 40 volatile compounds in the residue feed which was from microbial fermentation of wheat bran and other nutrients, including 2 alcohols, 8 acids, 5 aldehydes, 9 esters, 10 hydrocarbons, 3 ketones and 3 heterocyclic compounds. Biogas residue contains a small amount of volatile harmful compounds, while the types and contents of harmful compounds in residue feed decreased significantly after fermentation. The results showed that the nitrogenous compounds were non-volatile in biogas residue and residue feed, which was beneficial to preservation and utilization of the residue feed.