Ozone (O 3 ) and sulfur dioxide (SO 2 ) in a vertical column of the atmosphere in Thailand were obtained from the Brewers#121 and #120. There are similarities between the O 3 patterns obtained from the two sites, which are higher in the summer and rainy season compared with winter, although the magnitude of the change in Bangkok is greater than that in Songkhla. SO 2 values showed the summer months provide the higher SO 2 values in Bangkok, in contrast to Songkhla where the summer months give lower SO 2 values.