Industrial complexes are considered as a major source of hazardous air pollutants (HAPs) which include volatile organic compounds (VOCs), polycyclic aromatic hydrocarbons (PAHs), and heavy metals, etc. Therefore, the comprehensive monitoring and management of HAPs in the industrial complexes are required. In this study, the basic information of the industrial complexes (e.g., location, area, emission of air pollutants, meteorological conditions, and population) was used as input data for a geographic information system (GIS) software. On the basis of these GIS data, we proposed a systematic method for determining priority industrial complexes for the monitoring of HAPs. We identified 28 priority industrial complexes and classified them into four groups from level 1, whose HAPs should be continuously monitored, to level 4, whose HAPs do not have to be monitored. Furthermore, the case study of Ulsan was presented to demonstrate the selection procedure for sampling sites. The results of this study can be practically used to establish a long-term plan of the monitoring and management of HAPs.