Fatigue and friction and wear performances against Al—Ni—Bronze alloy for bare and coated 300 M steel were investigated with the application of WC coating into landing gear as background in this paper. The results indicated that both WC-17Co and WC-10Co4Cr coated 300 M steel exhibited comparable fatigue limit and cycles to fatigue failure with those of bare 300 M steel; while the fatigue limit and cycles to fatigue failure of 300 M steel were decreased by 120 MPa and 70 %~90 % respectively when 300 M steel was plated with chrome plating. The effect of coating on the fatigue property of 300 M steel was attributed to the propagation of fatigue crack in coating. Fatigue crack in WC coating deflected along the interface between WC coating and 300 M steel; while fatigue crack in chrome plating propagated into 300 M steel, provided as a sub-crack initiator and hastened the propagation of main fatigue crack in 300 M steel and finally led to the decrease of cycles to fatigue failure of 300 M steel. Friction and wear behaviors of coatings against Al—Ni—Bronze alloy lubricated by 10# aircraft hydraulic oil revealed that great volume loss was observed for Al—Ni—Bronze alloy and obvious mass gain was found for chrome plated 300 M steel when chrome plating was against Al—Ni—Bronze alloy; slight volume loss was obtained for WC coating, and the volume loss of Al—Ni—Bronze alloy against WC coating was only 1/50~1/100 of Al—Ni—Bronze alloy against chrome plating at all the three loads. The wear mechanism for WC coating and chrome plating against Al—Ni—Bronze alloy was respectively governed by abrasive wear and adhesive wear.