Using MoS2 as a lubricant and graphene(GE) as a lubricating additive,GE/MoS2 composite coatings with different content of graphene were prepared on the surface of GCr15 steel by spraying method.The tribological properties of the coatings were investigated by HSR-2M high-speed reciprocating friction and wear tester under dry condition and seawater environment,the wear scar morphology and wear mechanism were analyzed as well.The results reveal that the addition of appropriate content of graphene can significantly improve the tribological properties of MoS2 coatings,and the friction coefficient and wear loss of coatings in seawater environment are lower than that under dry friction.With the increase of graphene content,the friction coefficient and wear loss of GE/MoS2 composite coatings are decreased first and then increased in dry condition and seawater environment.The wear mechanism of MoS2 coating under dry friction is fatigue wear,adhesive wear and abrasive wear,and the GE/MoS2 composite coatings are mainly abrasive wear.However,only abrasive wear occurs in seawater environment for these coatings