This paper presents a comparative evaluation of efficiencies of different accelerated ageing tests (freeze-thaw, thermal shock, salt crystallization, dissolution and wetting-drying) and fuzzy inference system inpredicting weathering degrees of some monument stones from three historical sites (Anahita Temple,Anobanini reliefs and Eshkaft-e Salman reliefs, Iran). The combined effects of natural weathering pro-cesses (heating and cooling, wetting and drying, and freezing and thawing) and climatic information wereused for assessing the natural weathering degrees. Finally, the natural weathering degrees were multi-plied by time effect coefficients to obtain more realistic natural weathering degrees of the monuments.The predicted natural weathering degrees for Anahita Temple, Anobanini reliefs and Eshkaft-e Salmanreliefs are 56%, 61%, and 47%, respectively. These predicted values reasonably support the weatheringdegrees defined by progressive decay indices (calculated equal to 2.77, 3.42 and 2.66 for Anahita Temple,Anobanini reliefs and Eshkaft-e Salman reliefs, respectively), which means the fuzzy model potentiallycould accurately predict the weathering of stones.