Landfill site selection should take into account a wide range of alternative and evaluation criteria in order to reduce negative impacts on the environment. This study presents a geographic information systems-based multicriteria site selection of municipal solid waste (MSW) landfill in Ariana Region, Tunisia. The multicriteria decision integrates constraints and factors to select MSW landfill suitability. The methodology is used for ranking the best suitable landfill sites by the integration of fuzzy logic and analytic hierarchy process (AHP). The fuzzy set theory is used to standardize criteria using different fuzzy membership functions while the AHP is used to establish the relative importance of the criteria. The AHP makes pairwise comparisons of relative importance between hierarchy elements assembled by environmental and socio-economic decision criteria. The landfill suitability is accomplished by applying weighted linear combination (WLC) that uses a comparison matrix to aggregate different importance scenarios associated with environmental and socio-economic objectives. Data were assorted into five suitability classes within the study area, i.e., high, suitable, moderate, low and very low suitability areas, which represented 5.4, 0.5, 12.5, 3.9 and 2.5%, of the study area, respectively. Additionally, 75.2% was considered to be completely unsuitable for a landfill site. As a result, two candidate landfill sites are suggested.