In reference to water-safety-related theory and methods proposed on the basis of the karst region, the concept of water security, the establishment of the evaluation indicators of karst areas of water security system. Combining the advantages of system dynamics to establish a karst region prediction model simulation of water security. Precipitation for assessment of karst water security in the region and the sub-indicators of the overall system data. In reference to a large number of literature based on the karst region with the actual situation in the region to build a karst water security evaluation criteria. CRITIC method is established based on water safety index evaluation model - CRITIC Act empowers the use of indicators obtained from the bottom up, subsystem weights, and then through the composite index method to calculate the total system, subsystems, and water safety index. And to Qingzhen City as an example, an instance of evaluation, with the Bayesian method, attribute identification method have proved that the evaluation model is feasible, and the other models can be used in other parts of the assessment of water security for future research have a certain reference value.