This paper aims to examine the fatigue behavior of the Poly(methyl methacrylate)/ Acrylonitrile-butadiene-styrene (PMMA/ABS) polymer blends by means of experimental studies. For the material characterization of the blends, Thermogravimetric analysis (TGA), Fourier transform infrared (FTIR) spectrometry and Differential scanning calorimetry (DSC) investigations was used, which can reveal that the thermal and chemical properties of the blends. The Scanning Electron Microscopy (SEM) was used for fractographic analysis of fractured PMMA/ ABS blend specimens after fatigue tests. In this manner, the effects of ABS composition on the fatigue behavior of PMMA/ABS blends were investigated. The results showed that the number of cycles to failure for PMMA/ABS blends higher to pure PMMA, and fatigue strength of PMMA/ABS blends increased with ABS addition compared to pure PMMA. Also, the yield strength of PMMA/ABS blends decreased with increasing the ABS composition whereas total elongation increased. At the same stress amplitude, by increasing the amount of ABS composition in the blend structure, the number of cycles to failure increased 5.96 times. Finally, it can be concluded that the PMMA/ABS blends can be used in the needs of different designs for fatigue loading conditions in applications.