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<p>Ambient volatile organic compounds (VOCs) were measured continuously from January 2018 to December 2020 at an urban site in Zhengzhou (China) to investigate their characteristics, sources, atmospheric oxidation capacity (AOC), and chemical reactivity. During the sampling period, the total concentration of observed VOCs was <span class="inline-formula">94.3±53.1</span> <span class="inline-formula">µg m⁻³</span>, and alkanes were the major VOC species, accounting for 58 % of the total. During the sampling period, the interannual variation in VOCs gradually reduced from <span class="inline-formula">113.2±65.2</span> <span class="inline-formula">µg m⁻³</span> in 2018 to <span class="inline-formula">90.7±52.5</span> <span class="inline-formula">µg m⁻³</span> in 2019 and <span class="inline-formula">79.1±41.7</span> <span class="inline-formula">µg m⁻³</span> in 2020. Ethane and propane were the top two most abundant species during the 3-year observation period. Results showed that the total AOC, dominated by OH radical reactions, was <span class="inline-formula">7.4×10⁷</span> molec. cm<span class="inline-formula">⁻³</span> s<span class="inline-formula">⁻¹</span>. Total OH reactivity was 45.3 s<span class="inline-formula">⁻¹</span>, and it was mainly contributed by <span class="inline-formula">NO_<i>x</i></span>. The AOC and <span class="inline-formula"><span class="Radical">⚫</span>OH</span> reactivity both exhibited well-defined seasonal and interannual patterns. Therefore, control strategies should focus on the key species given their interannual and seasonal variations. Meanwhile, diagnostic ratios of VOC species indicated that VOCs in Zhengzhou were greatly affected by vehicle emissions and liquid petroleum gas/natural gas (LPG/NG). Positive matrix factorization analysis identified six sources: industrial sources, solvent use, vehicle emissions, LPG/NG, fuel burning, and biogenic sources. Vehicle emissions and industrial sources made the largest contributions to VOC emissions in each of the 3 years. The proportion of the contributions of vehicle emissions and LPG/NG increased with each passing year. However, the proportion of industrial and solvent sources presented a decreasing trend, which reflects the remarkable effect of control policies. The effect of VOCs on O<span class="inline-formula">₃</span> formation suggests that vehicle emissions and solvent use remain key sources. Therefore, it is necessary to formulate effective strategies for reducing ground-level O<span class="inline-formula">₃</span>, and those sources mentioned above should be strictly controlled by the regulatory authorities.</p>