Earthquake is one of the most important natural phenomena which we face it in Iran considering our situation with regard to faults. Planning for readiness to confront Consequences of earthquake is in work instruction of urban planners.to control crisis and decrease damages, crisis management are executed. Crisis management is one of the approaches of sustainable urban management.in crisis management and critical sustainable, decision making is very important. Therefore in this article with using of spatial decision support system (SDSS) vulnerability of Zanjan city to earthquake for executing crisis management before earthquake has being studied. Zanjan is one of the northern province of Iran which regard to geology maps, is one of the earthquake regions in our country. Components of using system in this project include: data base, (geographical information system), spatial analysis model (vulnerability model) and decision making quantities strategic planning matrix (Q.S.P.M). Effective variables in physical pathology in this study include: vulnerability of availability of open space, buildings density, the average components area and grading, buildings materials, buildings antiquity, physical structure and land using. At the end each of these variables based on their importance factors in GIS will be overlapping and final pathology map will be provided. Results shows regard to pathology over than 55 percent of Zangan s area is highly vulnerable to earthquake and the highest vulnerability relates to mineral fabrics that include district 1 and 2 and part of district 3 and 5 of zanjan. Eventually with regard to final goal of (SDSS) which is decision making, we use quantities strategic planning matrix (Q.S.P.M) to prioritize strategies for executing in highly vulnerable regions to earthquake.