Fatigue cracking and permanent deformation (rutting) are major distresses that occur in flexible pavements. One of the most significant solutions to prolong the fatigue life as well as rutting resistance for an asphaltic mixture is to utilize flexible materials such as fibers. The impact of fiber addition to hot-mixed asphalt (HMA) was investigated utilizing a developed testing program in which the mechanistic and mechanical performance of fiber-reinforced mixtures as well as the economic attributes were evaluated. All beam fatigue tests were strain-controlled tests performed according to current guideline procedures. The testing results indicated that the fiber-reinforced mixtures had a better performance compared with conventional mixtures in terms of rutting and fatigue resistance. Additionally, a mechanistic analysis coupled with a cost-effectiveness analysis study based on the fatigue and rutting resistance performance on the two mixtures was performed. Overall, analysis showed that fiber-reinforced asphalt mixtures exhibited significantly lower cost of pavement per 1,000 cycles of fatigue and rutting life 1.6 km (1 mi) compared with conventional HMA mixture.