This study investigates the trends and varieties of concentration of ozone in recent years in Taiwan in order to understand the situation of air qualities in different areas. Ozone is the secondary pollutant produced by nitrogen oxides, reactive hydrocarbons and sunlight. Because ozone has strong oxidizing power, it is easy to stimulate the respiratory system, which may cause cough, asthma, headache, tiredness and harmful to lung; and it is also harmful to plants and even synthetic materials. Here, we tried to study the trends and varieties of the time effect to the ozone level in each region and compare the similarities and heterogeneity of the models in different regions by the ozone data obtained from all air quality monitoring stations of environmental protection administration. Analysis of building appropriate temporal and spatial models are performed and factor analysis on the model residuals are used to investigate the possible latent variables to interpret the patterns of the ozone values in different regions. These may help to set up strategies for ozone control in the future.