To improve tribological property of MC Nylon6,the glass fiber and fly ash reinforced monomer casting nylon composites(GFFAPA)were prepared by anionic polymerization of ε-caprolactam.The friction and wear behaviors of composites under dry condition,water lubrication and oil lubrication were investigated through a ring-black wear tester.Worn surfaces were analyzed using a scanning electron microscope.The experimental results show that the tensile strength and hardness of nylon composites are obviously improved with reinforcement increasing.Compared to MC nylon,the lowest friction coefficient and wear rate of glass fiber reinforced nylon composites(GFPA)with GF30% respectively decrease by 33.1% and 65.3%,of fly ash reinforced nylon composites(FAPA)with FA20% decrease by 5.2% and 68.9% and of GFFAPA composites with GF30% and FA10% decrease by 57.8% and 89.9%.The main wear mechanisms of FAPA composites are adhesive and abrasive wear and of GFPA composites with high proportion are abrasive and fatigue wear.The worn surfaces of GFFAPA composites are much multiplex and the optional distributing glass fiber and fly ash have a synergetic effect on the wear resistance for GFFAPA composites.Compared with dry friction,the friction coefficient and wear rate under oil lubricated conditions decrease sharply while the latter reversely increase under water lubricated conditions.The wear mechanisms under water lubricated condition are principally chemical corrosion wear and abrasive wear and they become boundary friction under oil lubricated condition. To improve the tribological property of MC nylon 6, the glass fiber and fly ash reinforced monomer casting nylon composites (GFFAPA) were prepared by anionic polymerization of ε-caprolactam. The friction and wear behaviors of composites under dry condition, water lubrication and oil lubrication were Worn surfaces were analyzed using a scanning electron microscope. The experimental results show that the tensile strength and hardness of nylon composites are significantly improved with reinforcement increasing. Compared to MC nylon, the lowest friction coefficient and wear rate of glass fiber reinforced nylon composites (GFPA) with GF30% decrease by 33.1% and 65.3%, of fly ash reinforced nylon composites (FAPA) with FA20% decrease by 5.2% and 68.9% and of GFFAPA composites with GF30% and FA10% decrease by 57.8% and 89.9%. The main wear mechanisms of FAPA composites are adhesive and abrasive wear and of GFPA composites with high proportion are abrasive and fatigue wear. The worn surfaces of GFFAPA composites are much multiplex and the optional distributed glass fiber and fly ash have a synergetic effect on the wear resistance for GFFAPA composites. Compared with dry friction, the friction coefficient and wear rate under oil lubricated conditions decrease sharply while the latter reversely increase under water lubricated conditions. the wear mechanisms under water lubricated condition are principally chemical corrosion wear and abrasive wear and they become boundary friction under oil lubricated condition.