The atmospheric volatile organic compounds (VOCs) in Shenyang were observed in 2019, and the concentration characteristics and reactivity of 53 species were studied. The results showed that the average concentration of VOCs was 65.33 μg•m-3, and the proportions of alkanes, olefins, and aromatics were 62.44%, 16.52%, and 19.32%, respectively. The top ten species of VOCs were primarily C3-C5 alkanes, olefins, and some aromatics, accounting for 64.13% of the total VOCs. The concentrations of alkanes, alkenes, and aromatics in Shenyang showed a bimodal diurnal variation trend, with the peak values at 06:00-08:00 and 19:00-20:00 and the lowest values at 14:00-15:00. The highest (136.44 μg•m-3) and the lowest (35.61 μg•m-3) ρ(VOCs) occurred in December and May, respectively. The concentrations of VOCs showed an obvious seasonal variation: winter>autumn>summer>spring. In addition, alkanes, olefins, and aromatics showed an increasing trend with the seasons. Through the value of toluene/benzene (T/B), it was found that VOCs in Shenyang mainly come from traffic and combustion sources in spring, vehicle exhaust and solvent volatilization in summer, and biomass combustion and coal combustion in autumn and winter. It was found that combustion sources were the key to controlling ozone pollution in Shenyang, and propylene, ethylene, and 1-hexene are the most reactive species in atmospheric VOCs in Shenyang based on the analysis of reaction activity. © 2021, Science Press. All right reserved.