This research work focused on high-temperature properties of bituminous binders nano-reinforced by means of organoclays. A commercial organophilic montmorillonite was used as a second component to nano-reinforce a reference neat bitumen, and as a third component in a polymer-modified binder which was derived from the combination of the reference neat bitumen and a polyisoprenebased additive. Several mixing protocols were followed for blend preparation. Rheological behaviour of the binders was investigated by means of oscillatory and creep-recovery tests carried out with a dynamic shear rheometer. Results indicate that final properties of binders nano-reinforced with layered silicates are strongly affected by the mixing protocol adopted for blend preparation as a result of the key role played by the morphological configuration that nano-particles assume within the bituminous matrix.