In this study, numerical simulations using community multiscale air quality (CMAQ) were conducted to analyze the change in ozone (O3) concentration due to the reduction in nitrogen oxides (NOx) and volatile organic compounds (VOCs) emissions in Busan. When the NOx and, VOCs emissions were reduced by 40% and, 31%, respectively, the average O3 concentration increased by 4.24 ppb, with the highest O3 change observed in the central region (4.59 ppb). This was attributed to the decrease in O3 titration by nitric oxide (NO) due to the reduction of NOx emissions in Busan, which is classified as a VOCs-limited area. The distribution of O3 concentration changes was closely related to NOx emissions per area, and inland emissions were highly correlated with daily maximum concentrations and 8-h average O3 concentrations. Contrastingly, the effect of emission reduction depended on the wind direction. This suggests that the emission reduction effects may vary depending on the environmental conditions. Further research is needed to comprehensively analyze the emission reduction effects in Busan.