Abstract: The interface problem between carbon fiber and copper is very serious because of the poor wettability between carbon fiber and copper.Therefore the excellent performance of C_f/Cu composite is badly affected.The interface problem of C_f/Cu composite could be resolved when the carbon fiber is coated with copper through electroless plating and then mixed with copper.However it is very difficult to deposit copper onto carbon fiber because carbon fiber was tenuous and hydrophobic. The effect of four kinds of additives A（alkyl benzene sulfuric salt）,B（alkyl sulfuric salt）,C（dodecyl fatty salt）and D（dodecyl fatty salt + sodium acetate） was discussed respectively when bluestone was used as main salt and zinc as reducing agent to deposit copper onto carbon fiber. The result showed that additive D was the best one in copper plating and the problem of black-core that often occurred in the course of copperizing a bundle of carbon fiber was effectively resolved.SEM showed that every carbon fiber was coated with even and continuous copper in the experiment,the interface bonding between carbon fiber and copper was firm, and carbon fibers combined with copper tightly in the composite.