Abstract: The purpose of this study is to evaluate the effect of fiber type and content on the rutting performance of stone matrix asphalt mixtures. In this research two types, cellulose fibers (made in Iran and Germany) and mineral fibers (rock wool) with various percentages (0.1-0.5%) of the total weight of the Stone Matrix Asphalt (SMA) mixture were used and after determining optimal bitumen content for each fiber percentage, we examined their effect on SMA bulk specific gravity, Void in Mineral Aggregate (VMA), void content, Marshall stability, Indirect Tensile Strength (ITS) and flow parameters. Also results of dynamic creep test were used as an indicator of rutting performance of SMA specimens. Results of the laboratory tests showed that variation of fiber type and content can lead to considerable changes in rutting performance of SMA. Specimens made with 3% cellulose-GER (made in Germany) has resulted to highest value of ITS and least permanent deformations. Also with considerations of potential rutting, optimum percentage for each fiber type has been concluded.