The study on vulnerability plays an important role in planning of prevention and mitigation, and risk management of regional disasters. He'nan province, suffered from frequent natural disasters, was taken as the study area, and the prefecture-level cities as basic assessment unit. Eleven independent impact factors were selected using rank correlation analysis and PCA(principal component analysis) method, and the assessment model of social vulnerability was constructed. The relative weights of each index were determined using the AHP(ainalytical hierarchy process) method, and the social vulnerability to natural disasters of each unit was assessed using the comprehensive index method. The assessment results were mapped and studied using ArcGIS software. The results showed that:(1) The social vulnerability to natural disasters presented a certain regional distribution pattern.(2) Zhoukou City, Shangqiu City and Zhumadian City were in higher social vulnerable area, belongs to level Ⅲ, Zhengzhou City, Jiyuan City and Sanmenxia City were in lower social vulnerable area, the levelⅠ, and others were in moderate social vulnerable area, the level Ⅱ.(3) The area ratio of He'nan Province in higher, moderate and lower social vulnerable area was 22.68%, 65.35% and 11.97%, respectively.