Satellite remote sensing is increasingly applied in the field of environmental protection, especially in atmospheric monitoring. The objective of this study is to monitor Thailand’s atmospheric environment by Satellite remote sensing: Carbon Dioxide (CO₂) case study over a 5-year period from 2017 to 2021. Data from Greenhouse gases Observing Satellite (GOSAT) was used to analyze atmospheric CO₂ concentration using Map Algebra and Interpolation. The results were then analyzed together with relevant environmental factors, including altitude, temperature, rainfall and season. The results showed that (1) CO₂ concentration was highest in 2021 with the annual average of 409.903 ppm and lowest in 2017 with the annual average of 401.109 ppm, (2) Analysis based on the height above sea level showed that the lowest CO₂ in 2017 was 403.480 ppm, the highest in 2021 was 412.896 ppm, (3) Analysis together with relevant environmental factors such as altitude, temperature, rainfall and season revealed that Thailand’s monthly average CO₂ concentration fluctuates over a year depending on the season. It was found that during winter and summer, CO₂ concentrations fluctuated with temperature values. In addition, during the rainy season, atmospheric CO₂ decreases due to increased plant photosynthetic rates; as a result, CO₂ in the atmosphere is consumed and converted into carbon dioxide in the form of wood.