In the present work, large amplitude oscillatory shear (LAOS) coupled with Fourier transform rheology (FTR) were used for the first time to characterize the nonlinear rheology of bituminous binders, including two polymer modified bitumens (PMB) containing EVA and HDPE. Additionally, a brief study in the linear regime was done to complete the rheological characterization along with morphological characterization of PMBs by means of fluorescent optical micrographs. The comparison between the LAOS-FTR characteristics of samples was done using a rheological approach (all binders compared at either same phase shift angle δ or same Deborah number, De) and an experimental approach (all binders compared at same frequency). In all the approaches, EVA PMB had the lowest nonlinear levels compared to HDPE PMB. Furthermore differences in the nonlinearity among PMBs, parent 70/100 pen grade bitumen, and benchmark 35/50 pen grade bitumen were also found. The LAOS-FTR fingerprint of bituminous binders, though unique, held some similitudes with the reported FTR spectra of multiphase and polymeric systems. For characterization of asphalt binder in the nonlinear regime, the strength of LAOS-FTR technique over stress relaxation one was confirmed, not only in terms of the sensitivity but also in terms of the results interpretation. Furthermore LAOS-FTR was used to analyze time sweep data with the aim to propose FTR quantifiers as indices to predict fatigue performance.