The rheological study of bitumen is essential to improve the performance of pavements. Bitumen properties are traditionally determined by means of dynamic shear rheometer measurements. In this work, we aim to demonstrate that atomic force microscopy (AFM) can be a powerful complementary tool to the characterisation of bitumen. In particular, we compare the mechanical properties of pure and modified bitumen. Two different anti-oxidant additives were used: PPA (poly-phosphoric acid) and LCC (cashew nut oil) at concentrations of 1% and 2%, respectively. We will show that the AFM technique is able to distinguish the effects of both additives in the morphological and micromechanical properties of bitumen films.