Osteoarthritis originates and progresses with changes in surface topographies and mechanical properties of cartilage. This study was aimed to characterise cartilage surface topography and its changes with wear progression at a nano-scale. Cartilage samples were generated in wear tests. Three dimensional (3D) cartilage surface data was obtained using atomic force microscopy (AFM) and then quantitatively characterised using both conventional and feature parameters. The results have given a new insight to the wear process which could not be achieved previously.