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Flood control and disaster reduction is one of the eternal theme of human society. Due to the inevitability of the flood, people can only manage the flood, to avoid the risk and reduce losses. Flood risk assessment based on the premise of the flood risk management and important part of the strong support of the flood control and disaster mitigation decision-making, especially for flood disaster-prone areas with high frequency of great significance. Floods, river floods are the most important part. Is located in the southeast coast of China, Quanzhou, Fujian Jinjiang River is one of the flood-stricken areas are more prone to. Based on the flood system theory point of view, starting from the hazards, disaster - environmental disaster bearing body, build the hierarchy of the flood risk assessment and quantitative indicators, the background of basic geographic data, rainfall data, socio-economic statistics based on the integrated use of the Analytic Hierarchy Process (AHP), multi-layer fuzzy comprehensive evaluation method (MFSE), GIS spatial analysis and modeling techniques, the establishment of the Jinjiang River flood risk assessment model. The Jinjiang River floods risk evaluation, and thus the evolution of flood risk analysis. The main results show that: the correlation of the Jinjiang River flood hazard and rainfall, topography and river network, followed by; and the more downstream and flat area, the greater the impact of terrain and river flood risk. Jinjiang River floods risk from northwest to southeast, gradually increased, the more the higher the risk of downstream estuaries. High risk and high-risk area of ??the entire watershed ratio of the sum of 40.84%, a larger proportion; mainly distributed in all of Licheng District, Jinjiang City, the northern, central and north of Nanan City, Anxi County, east and southeast of Yongchun County department. County district floods mean risk index in descending order: Jinjiang City, Licheng District, Fortress District, Nanan City, Dehua, Yongchun County, Luo Jiang, Anxi County. Jinjiang River flood risk during the 2000-2006 level did not change significantly. High-risk areas and the increase in high-risk areas, and the remaining risk areas has decreased, but not by much. The magnitude of risk change is a high-risk area. Than the increase in flood risk areas and increase in flood risk areas accounted for 24% of the total area of ??the whole basin. Changes in basin-wide flood risk index mean of 0.0124. Fortress, Licheng District, Jinjiang City flood risk mean variation are far more than the mean of the whole basin is an increased risk of a relatively large number of areas.
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