Abstract: A new complex cheminescence, i.e. Luminol H₂O₂ catalyzed by CuR₂^2- complex was reported. The linear range for the determination of Cu(Ⅱ) is 1×10^-10～1×10^-7g/mL. The detection limit is 6.6×10^-11 g/mL. The relative standard deviation (n=5) for an analytical concentration of 4×10^-8 g/mL is 2.7%. The tolerable capacity of interserence ion is relatively large.The precision, accuracy and selectivity of the method are very good.The mothod has been used to determine trace copper with satisactory results.