Recognizing potential sites for landfill has increasingly become an important waste management strategy around the world. This study aims to determine municipal solid waste (MSW) landfills in SaharKhiz Region located in Gilan by comparing Fuzzy logic and Boolean logic. Fuzzy logic, which has been used in this research, is based on weighted linear combination (WLC); however, the utilized Boolean logic is considered only to determine the accuracy and validity of every method. At first, the Boolean logic using a geographical information system (GIS) is used to recognize potential and excluded zones, based on zero and one value system. In the next phase, Fuzzy logic is used, between zero and one, to standardize information layers, based on their type (increasing or decreasing). The final weight of every layer was determined using the analytical hierarchy process.
Finally, the WLC method was used to integrate layers in the GIS environment to provide the final site suitability map in five classes of Fuzzy membership degree. The results show that Fuzzy logic, based on WLC, has more flexibility to resolve conflicts of human judgment, and it also has higher accuracy than Boolean logic in the selection of optimal landfill sites for MSW in SaharKhiz Region, Gilan Province, based on ecological and socioeconomic parameters.