Abstract: A method of single scanning oscillopolarography for the successive determination of Cu and Zn in four kinds of wild plants in a medium of HCl-KCNS was described in this paper.Two sharp second derivative polarographic waves were appeared at -0.42 V (vs.SCE) for Cu and -1.03 V (vs.SCE) for Zn.Detection limits were 0.005 mg·L-1 for Cu and 0.01 mg·L-1 for Zn.Linearity of the calibration curves was in range of 0.01-800 mg·L-1 for Cu and 0.01-10.00 mg·L-1 for Zn.The method has been applied to the determination of Cu and Zn in wild plants of codonopsis lanceolata benth et hook,astragalus membranaceus,cortex dictamni and fern with results of good precision (RSD<2.5%) and accuracy (recoveries >97%).