Iron is one of the important metal mineral resources in Jiangsu Province. According to the latest principles of geological prospecting, to highlight the deep and blank areas for ore-prospecting and open up the prospecting ideas of “the second ore formation space”. Guided by the new theory and the secondary use of geological data to enhance the strength and depth of development, the authors made a full use of geological prospecting technologies inclusive of geophysical, geochemical, remote sensing and other new technological methods for the assessment of potentiality assessment of iron resource. By this assessment, six long-term survey areas, six key survey areas and eight census verification areas were delineated.