The difficulty frequently encountered in flood disaster evaluation is that there are so many factors included and the complex interrelationship existed among them.The evaluation cannot be achieved according to only one factor,because all the effect factors associated with flood disaster must be thought over.However,up till now,there is no a unified standard of assessment index system in the world.The research shows that projection pursuit model could form a suitable index for overcoming the difficulties in assessment.Projection pursuit is a statistical technique,which is by projecting high-dimensional data onto low-dimensional space and most of data's feature can still be retained by a main characteristic component.It makes the assessment of high dimensional feature easier.For the first time,an efficient approach with genetic algorithm to find interesting projection is offered in this paper.Using this new model,we succeeded in analyzing1998flood characters in China,and evaluating flood disasters from1989to1990in33provinces in China.