The New Hail Economic City in the Kingdom of Saudi Arabia is one of the pioneer projects and represents a corner stone for the new development activities for Hail region. It is located to the north of the Hail city, covering an area of ~156 km2. Fundamental facilities of this project will include infrastructure, residential, commercial, industrial, and a new international airport. The present study aims to establish a new approach of site investigation using engineering geologic mapping and geological hazard evaluation. To achieve this approach, physical and engineering characteristics of surface and subsurface soil and/or rocks of the study area were evaluated. Several data sources were used including: geologic and topographic maps, satellite images, previous data and reports, and detailed field and laboratory investigations of soil and rocks. Our finding indicated that the study area is characterized by soil layer which varies in thickness from 0 to 12 m and rock outcrops. An engineering geology mapping of the new economic city was prepared using GIS environment. It classifies the area into six zones (4 for soils and 2 for rock outcrops) according to their physical and geotechnical properties. Three cross sections were prepared according to subsurface data showing the layers variations within the study area. Finally, the geological hazards causing negative impact on the area were identified. Various recommendations were proposed to help project decision makers to deal with the geological and geotechnical problems.