Resinbased friction composites with different porosity percentage were fabricated by mould pressing process.The effects of porosity percentage on the mechanical properties of the composites and the tribological behaviors under dry friction were investigated.Experimental results show that with the porosity increasing,the surface roughness of the composite is significantly increased,while shear strengthen and compressive strengthen are decreased.The friction coefficient of the composite with different porosity percentage has different trends at different temperatures,it is firstly increased and then decreased with the porosity increasing at low temperature,firstly decreased and then increased at high temperature.However,the porosity percentage has less effect on friction coefficient at medium temperature.The composites with low porosity percentage have higher and more stable friction coefficient,which exhibit much lower wear rate.