The lubricated rolling wear was simulated using a specially modified pin-on-disc tester. Wear particles were collected in running-in and steady state wear stage, and analysed using a particle analyser, ferrography, confocal laser scanning microscopy and computer image analysis techniques. Numerical parameters, R-a, R-q and R-sk were used to measure the evolutions of the surface alternations from the running-in to steady state wear stage. Quantitative data on the evolutions of the surfaces of both the wear debris and the wear components were presented in the paper. The knowledge obtained in this research is important for predicting wear conditions using wear debris analysis techniques, while further understanding of the wear mechanisms and wear characteristics has been also gained. (c) 2004 Elsevier B.V. All rights reserved.