The　pharmaceutical　factory,　brewery　and　rubber　factory　were　selected　to　measure　the　chemical　characteristics　of　VOCs　emissions　from　their　different　production　processes.　The　results　indicated　that　in　the　pharmaceutical　factory,　VOCs　emitted　from　analgin　synthesis　and　aminopyrine　synthesis　were　mainly　composed　of　benzene,　toluene,　styrene　and　other　aromatics,　and　VOCs　emitted　from　acetaminophen　synthesis　were　mainly　composed　of　C4-C6　alkanes.　VOCs　emitted　from　brewery　and　rubber　factory　were　both　characterized　by　toluene,　ethylbenzene　and　p-xylene.　Moreover,　the　maximum　incremental　reactivity　method　was　applied　to　analysis　the　ozone　formation　potential　of　VOCs　emissions　from　these　factories.　The　dominant　species　for　ozone　formation　were　benzene,　toluene　and　other　aromatics　for　the　analgin　synthesis　and　aminopyrine　synthesis　in　the　pharmaceutical　factory;　c-2-Butene,　toluene　and　isopentane　for　the　acetaminophen　synthesis　in　the　pharmaceutical　factory;　toluene,　ethylbenzene　and　m,　p-xylene　for　the　brewery　and　the　rubber　factory,　respectively.　The　threshold　of　diluted　multiples　was　also　used　to　analysis　the　stench　index　of　these　VOCs　emissions.　The　results　showed　that　the　odor　pollution　in　the　pharmaceutical　and　brewery　was　relatively　slighter.　However,　the　telescopic　device　and　vulcanizing　workshop　in　the　rubber　factory　were　influenced　by　a　certain　degree　of　odor　pollution.　©,　2015,　Zhongguo　Huanjing　Kexue/China　Environmental　Science.　All　right　reserved.