Abstract: Abstract: The composting process has a characteristic of high concentrations of volatile organic compounds (VOCs) emission. However, the site monitoring data about emission of VOCs during swine manure composting process is relatively limited and the baseline is also ambiguous at present. The composting bins were aerated with ventilation rate of 60 L/(m3•min), the experiment lasted for 31 days from October to November 2015 in Beijing. The daily ambient temperatures ranged from 3.74 to 13.76 ℃during the entire experimental period. The daily average temperature inside each composing bin rose and exceeded 50 ℃ within 4 days, and kept above 50 ℃ for 28, 28 and 23 days, respectively, which could secure pathogen inactivation and meet the non-hazardous requirement of national standards. The gas samples were collected using SUMMA canisters, and GC-MS was utilized to analyze the concentrations of VOCs. The results showed that 81 kinds of VOCs were detected, including dibutene, butane, cis/anti-2-butane, 1-butylene, isopentane, amylene, n-pentan, anti-2-pentene, isoprene, cis-2-Pentenenitrile, 2,2-dinethyl butane, 2,3-dimethylbutane, 2-methylpentane, cyclopentane 3-methylpentane, n-hexene, hexane, 2,4-dimethylpentane, methylcyclopentane, cyclohexane, 2-methylhexane, 2,3-dimethylpentane, 3-methylhexane, 2,2,4-Trimethylpentane, heptane, methylcyclohexane, 2,3,4-trimethylpentane, 2-methyl heptane, 3-methylheptane, octane, nonane, decane, undecane, dodecane, trimethylamine, dimethylsulfide, dimethyl disulfide, dimethyl trisulfide, freon 11, freon 13, freon 114, isopropyl benzene, propylbenzene, between-ethyl toluene, ethyl toluene, mesitylene, ortho ethyl toluene, pseudocumene, 1,2,3- three methyl benzene, diethylbenzene, two ethyl benzene, benzene, methylbenzene, chlorobenzene, ethylbenzene, m/p-xylen, ortho-xylene, styrene, 1,3-dichlorobenzene, 1,4-dichlorobenzene, 1,2,4-trichlorobenzene, naphthalene, vinyl chloride, methyl bromide, ethyl chloride, 1,1-dichloroethylene, dichloromethane, 1,1-dichloroethane, cis-1,2- two vinyl chloride, chloroform, 1,1,1-trichloro ethane, carbon tetrachloride, 1,2-dichloroethane, trichloroethylene, 1,2-dichloropropane, anti 1,3-two chloride, cis-1,3-Dichloropropene, 1,1,2-trichloroethane, tetrachloroethylene, 1,2-dibromoethane, tetrachloroethane. Among these 81 VOCs, the varieties of alkanes, aromatic compounds, halohydrocarbons, amines, sulfur compounds and freon compounds were 34, 21, 19, 1, 3 and 3, respectively. In addition, trimethylamine, dimethyl sulfide, dimethyl disulfide and dimethyl sulfur had higher detection rate and the concentrations of them were far more than their olfactory threshold, their emission peak were 2.711, 2.479, 5.479, 2.204 mg/m3, respectively. During the composting process, the emission of VOCs focused on the first 2 weeks. Next, we need to study the emission of VOCs from pig manure with different feedstocks and different composting conditions. The study provides data support for mitigating VOCs gas emissions during the composting of pig manure.