AbstractBayesian statistical inference with a case-crossover design was used to examine the effects of air pollutants {Particulate matter <10 μm in aerodynamic diameter (PM₁₀), sulphur dioxide (SO₂) and ozone (O₃)} on mortality. We found that all air pollutants had significant short-term impacts on non-accidental mortality. An increase of 10 μg/m³ in PM₁₀, 10 ppb in O₃, 1 ppb in SO₂ were associated with a 0.40% (95% posterior interval (PI): 0.22, 0.59%), 0.78% (95% PI: 0.20, 1.35%) and 0.34% (95% PI: 0.17, 0.50%) increase of non-accidental mortality, respectively. O₃ air pollution is significantly associated with cardiovascular mortality, while PM₁₀ is significantly related to respiratory mortality. In general, the effects of all pollutants on all mortality types were higher in summer and winter than those in the rainy season. This study highlights the effects of exposure to air pollution on mortality risks in Thailand. Our findings support the Thailand government in aiming to reduce high levels of air pollution.