The　air　quality　of　Handan,　a　typical　industrial　city　in　China,　has　been　significantly　improved　through　atmospheric　pollution　control,　except　for　ozone　(O-3)　pollution.　We　found　that,　in　summer,　emissions　of　anthropogenic　volatile　organic　compounds　(VOCs)　and　NOx　decreased　yearly　in　Handan,　but　the　O-3　concentration　significantly　declined　yearly　during　2013-2015,　whereas　it　experienced　worsening　O-3　pollution　after　2015.　Therefore,　we　used　the　Weather　Research　and　Forecasting　Community　Multiscale　Air　Quality　(WRF-CMAQ)　modeling　system　to　simulate　the　influence　of　the　meteorological　conditions　and　emission　changes　in　Handan　during　the　typical　period　(June)　of　O-3　pollution　in　2013-2018.　For　benchmarked　June　2013,　the　results　showed　that　the　reduction　of　the　O-3　concentration　in　June　of　2014-2016　was　mainly　caused　by　emission　reduction,　while　in　June　of　2017-2018,　the　combined　effect　of　changes　in　emissions　and　meteorological　conditions　led　to　aggravated　O-3　pollution.　Sensitivity　analysis　indicated　that　combined　VOCs　and　NOx　emission　controls　would　effectively　reduce　incremental　O-3　formation　when　the　abatement　ratio　of　VOCs/NOx　should　be　no　less　than　0.84,　and　we　found　that　VOCs　reduction　would　continusouly　bring　about　O-3　decreases　under　various　NOx　reductions,　but　its　positive　sensitivity　to　O-3　would　become　smaller　with　NOx　reduction.　However,　the　positive　influence　of　NOx　reduction　on　O-3　would　happen　until　NOx　reduction　exceeding　45-60%.　The　findings　will　be　helpful　in　formulating　emission　control　strategies　for　coping　with　O-3　pollution　in　an　industrial　city.