Recently, a worse and large-scale forest fire broke out across Turkey, which adversely affected the country’s air quality level and caused a tremendous loss. Mugla and Antalya cities were the hot spot areas of this fire that experience adverse effects. In this paper, we examined and compare the air pollution scenario before and during the forest fire episode i.e., from 27 July to 10 August 2021 in Antalya and Mugla. The results show that before the fire accusation, i.e., on 27 July, the daily mean aerosol optical depth (AOD), was 0.1 indicates a clear sky. However, as the fire breakouts on 28 July, this daily mean AOD value increased too rapidly and reached 0.52 on 6 August, indicating intense air pollution. The highest AOD was 2.2 over northern Marmaris, Ula, southeastern Milas, Mugla Merkezon on 5 August 2021. The results show that peak fire activity occurred during 4–8 August. Meanwhile, the highest NO2 concentration was 167 µmol/m2 over mid-east Merkez and Köycegiz. The peak HCHO load was 750 µmol/m2 over southern Mugla city. Moreover, Mugla and central Antalya cities experienced the highest O3 concentrations of 0.14 µmol/m2. Similarly, at the Junction of Dalaman, Köycegiz, and Ortaca, peak CO (0.08 mol/m2) and AI (3.5) had been observed. The high-altitude smoke was over Mugla city. Whereas, over Antalya, mixed aerosols had dominant, followed by smoke, dust, non-smoke fine mode, and fine dominated aerosols.