Abstract: By coupling meso-scale meteorological model and high-resolution chemicasl model, we studied the characteristics of spatial and temporal distribution and variation of ozone in Guangzhou.The results showed that the distribution of O\-3 in the lower layer of troposphere has a good relation with that of the surface emission and indicated the multi-center distribution.Local O 3 concentration has a good diurnal cycle.It gave a good agreement between the simulated results and monitoring results.The analysis of vertical O\-3 concentration profile of mono-station showed that O\-3 concentration has higher range of diurnal change in lower layer of troposphere.