Objectives : Using a mobile laboratory equipped with Proton Transfer Reaction-Time of Flight/Mass Spectrometry (PTR-ToF-MS), we investigate the degree of air pollution level in the petrochemical industrial complex by investigating the distribution characteristics of air pollutants and tracking emission sources.Methods : The research area within the petrochemical industrial complex was measured three times each at dawn, day, night, and the distribution of VOCs at each time was investigated and presented as a pollution map. In the emission source tracking, hot spot (high-concentration) wes found by mobile monitoring, and the emission source was closely tracked by stationary monitoring.Results and Discussion : Acetaldehyde measured in the petrochemical industrial complex was confirmed to have the highest 3 to 5 degrees by direct olfactory method. In most instances the highest concentration was at dawn, potentially due to stagnant pollutants caused by temperature reversal. It was observed that the probability of finding an hot spot was higher during dawn and that it was significantly affected by the wind direction and speed at the time of measurement. When tracking the emission sources, appropriate areas of concern for contamination were selected on the basis of the stationary monitoring results, which were obtained from areas showing high concentrations after mobile monitoring.Conclusion : As a result of the investigation of the distribution characteristics and emission sources of air pollutants in the petrochemical industrial complex, we found that acetaldehyde was the major pollutant and presented an efficient method to search for areas of concern for air pollution. Through these results, it is expected that emission sources can be managed more efficiently.