Emissions of ozone precursors (NO x and VOCs) and photochemical ozone creation potentials (POCPs) of VOC emission sources were investigated in the largest port city (i.e., Busan), Korea during the year 2011. This analysis was performed using the Clean Air Policy Support System (CAPSS) national emission inventory provided by the National Institute of Environmental Research (NIER), Korea. For NO x , the emissions from off-road mobile sources in Busan were the most dominant (e.g., 31,202 ton yr −1 ), accounting for about 60% of the total NO x emissions. The emission from shipping of off-road mobile sources (e.g., 24,922 ton yr −1 ) was a major contributor to their total emissions, amounting to 47% of the total NO x emissions due to the port-related activities in Busan. For VOCs, the emission source category of solvent usage was predominant (e.g., 36,062 ton yr −1 ), accounting for approximately 82% of the total VOC emissions. Out of solvent usages, the emission from painting was the most dominant (22,733 ton yr −1 ), comprising 52% of the total emissions from solvent usages. The most dominant VOC species emitted from their sources in Busan was toluene, followed by xylene, butane, ethylbenzene, n-butanol, isopropyl alcohol, and propane. The major emission sources of toluene and xylene were found to be painting of coil coating and ship building, respectively. The value of POCP for the off-road mobile source (61) was the highest in ten major activity sectors of VOC emissions. Since the POCP value of ship transport of off-road mobile source (72) was also high enough to affect ozone concentration, the ship emission can play a significant role in ozone production of the port city like Busan.