Ozone gas concentration measured at that point is equal to 87.06 μg/Nm3. The lowest ozone gas concentrations measured at Padang City is equal to 6.32 μg/Nm3 at 48 sampling points located in Bukit Gado-Gado. The average concentrations of measurement is 25,67 μg/Nm3. The highest concentration of ozone gas was measured at 87.06 μg/Nm3, where the concentration is still below the quality standard. It shows that the concentration of ozone in the area of Padang is in the range that does not harm the air.