The objective of the study is to produce preferential impact assessment factors for Environmental Impact Assessment by considering regional features and public participation in the initial stages of EIA. In order to produce preferential impact assessment factor, the study was carried out through theoretical research and a survey of public awareness as way to reflect public participation based on theoretical research. The survey of public awareness was conducted in the form of an interview to review the impact which the construction of atomic power plants at Hyo-am village, Jang-an, Kyungsang Province and Bi-hak village, Suhsang-myon, Ulsan-Kun will have on the surrounding environment : to reflect public participation on deciding preferential assessment: and to determine the extent of alternatives of the proposed project. As the result of the study, the followings were identified as preferential assessment factors in the displacing settlement and surrounding areas: cultivation marine products, change of temperature of seawater due to flow of warm water, land use (negative), noise vibration during construction, existing vegetations, erosion sedimentation, influx of manpower for construction(negative), recreation landscaping during construction and operation, change in flow of transportation during construction, the quality of seawater during construction and operation were produced as preferential assessment factors in both displacing area and neighboring areas. In the displacing settlement area, the educational environment(negative & positive) and positive aspects of the influx of manpower for construction were also identified as preferential assessment factors.