Real Estate analysis in urban area is an important and very difficult task. The value of a property is primarily determined by its location. Thus a geographical information system (GIS) is of great importance in the evaluation process. In the last decade a very promising approach of dealing uncertainty in real estate analysis is Fuzzy theory due to the need of handling the large number of qualitative and quantitative variables that affect the value of an estate. This paper discusses the architecture for a decision support system for Real Estate analysis based on GIS techniques integrated with Fuzzy theory. In order to evaluate the system data were used from the urban area of P. Faliro in Attica basin of Greece.