Abstract: 109 volatile organic compounds (VOCs) in the ambient air of Tianjin Industrial Area were monitored offline from March 2021 to August 2021 by thermal desorption gas chromatography-mass spectrometry method. The composition characteristics, ozone formation potential (OFP) and sources of VOCs were studied, and refined analysis of industrial emission sources was carried out. The results showed that VOCs concentrations fluctuated between (46.6±19.7) and (136.8±55.7) µg/m³ during the observation period, with alkanes, halogenated hydrocarbons and oxygenated volatile organic compounds (OVOCs)contributing more to VOCs concentrations, and alkanes and aromatic hydrocarbons showed a daily trend of low at noon and high in the morning and evening, while OVOCs did the opposite. Alkanes, aromatic hydrocarbons, olefin and OVOCs accounted for a large proportion of OFP contribution, the contribution proportions of alkanes to OFP were mainly influenced by their percentage of concentration, the contribution proportions of aromatic hydrocarbons and olefins to OFP was significantly higher in summer, and their emission control should be strengthened in order to control ozone (O₃). Source apportionment showed that the main emission sources in spring and summer were industrial sources, solvent use sources, diesel vehicle exhaust emissions sources, oil vapour volatilisation sources and natural sources. The refined analysis of industrial sources showed a positive correlation between the concentration of aromatic hydrocarbons and the production of coke and soda ash, a positive correlation between the concentration of OVOCs and the production of natural gas, ethylene and agricultural nitrogen, phosphorus and potassium fertilizers, a positive correlation between the concentration of halogenated hydrocarbons and the production of natural gas, automobiles, agricultural nitrogen, phosphorus and potassium fertilizers, and soda ash, and a positive correlation between the concentration of olefins and the production of power generation equipment. It was preliminarily determined that the aromatic hydrocarbons, OVOCs, halogenated hydrocarbons and olefins in the ambient air of the region were likely to come from these significantly correlated sub-segments of industrial enterprises.