This study investigated the PET yarns which were coated with different ratio of primer and plated aluminum in vacuum. To study the effect of anti-electrostatics, strength and elongation of plating aluminum yarns, various compositions of aqueous P.D. and aluminum ion were presented to different groups of primer.The experimental results indicated that the anti-electrostatics effect took better when the ratio of aqueous P. U. or aluminum ion were inereased; while the strength and elongation of yams were decreased, when the amount of alkali agent were increased for pretreatment of yams.