Carbon fibre forged composite ( CFFC) with epoxy matrix was prepared with moulding pressing technology． The friction performance of the CFFC under dry and water-lubricated friction conditions were comparatively investigated． The variations of the friction coefficient under these two friction conditions were studied，and the micro wear mechanism of the CFFC was analyzed． Ｒesults show that the friction process of CFFC exhibits different trends under these two conditions． The friction process in dry friction can be divided into three stages，including an initial stability stage，a transfer film formation stage and a stabilization stage，during which an iron-containing transfer film possesses a self-lubricating effect． While in water-lubricated friction，the friction behaviour of CFFC is dominated by a water-lubricated film，which could help its friction process rapidly develop into the stabilization stage． A smaller friction coefficient and a lower and more stable wear rate of CFFC are obtained under the water-lubricated friction condition． In addition，the reduction rates of friction coefficient are basically the same under two friction conditions．