Abstract: Tire wear particles were collected by a newly designed test rig. The size and morphology of the wear particles as well as surface topography under different conditions (e.g. load, velocity and inflation pressure) were investigated via optical microscope and scanning electron microscope. The results show that the particle size distribution of wear particles was similar to normal distribution and the particle size was mainly between 100 μm and 300 μm. The tire particles were produced by tread fatigue wear (lamellar spalling and curl wear). The curl wear was the main contribution of wear particles. The dominant wear mode (lamellar spalling and curl wear) depended on normal load. Increasing contact stress increased the number of large-sized wear particles while increasing velocity increased the number of small-sized wear particles. The influences on number of wear particles with size less than 10 μm depended on velocity, inflation pressure and load. The study provided theoretical guideline for reduction of the secondary hazard of wear debris caused by tire wear．