The differential absorption lidar is an effective tool for measuring ozone distributions. In the haze event, the differential absorption lidar is carried out to observe the temporal and spatial distribution characteristics of ozone concentration. The results show that a high ozone pollution process is caused by southwest airflow together with the influence of subtropical anticyclone in mid June. From the night of June 14 to midday of June 15, ozone concentration in high altitude reaches above 1.2×10-7. And the ozone gas ranging from 1.5 km to 2 km moves down to the surface, thus causing the increase of surface ozone concentration afternoon on June 15. In the haze period, the distributions of fine particulates and ozone show different characteristics in different heights. Specifically the near-ground particles completely participate in the photochemical reaction process, while particles and ozone with are more related to transportation. In addition ozone concentration in clear weather is low and no obvious external input air mass is observed.