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Heavy metals are considered to be hazardous pollutants with toxic effects on plant and/or human health. Different techniques and methods (e.g., AAS, ICP-MS, ICP-OES) have been utilized for trace metals determination in the laboratory, but they are characterized by high costs, complex operation and long time consuming. The demand of rapid on-site screening and assessment of agricultural land contaminate induced by heavy metal is highly desirable. This paper reported a fast, inexpensive electrochemical analysis method for the simultaneous determination of cadmium (Cd) and lead (Pb) in soil samples. A simplified soil extraction procedure, using 0.11 molL-1 acetic acid and a 1 h ultrasonic agitation, had been used to fulfill the requirements of field-based screening usage. A disposable sensor, incorporating a three-electrode configuration (working electrode, reference electrode and counter electrode), had been fabricated by low cost screen-printing technology. The surface of graphite carbon working electrode was judiciously modified by multiwalled carbon nanotubes(MWCNTs)/Nafion/bismuth coating. Coupled with the portable electrochemical instrument, trace detection of heavy metal ions had been carried out by square wave anodic stripping voltammetry (SWASV) technique. The electrode exhibited good sensibility and stability in the electrochemical measurement. Linear responses were obtained in the range from 1 to 80 gL-1 for both the metal ions at a preconcentration time of 180s, with detection limits of 0.5 gL-1 for Cd(II) and 0.8 gL-1 for Pb(II), respectively. The relative standard deviation is 1.9% and 2.3% for 20 gL-1 each of Cd(II) and Pb(II).Soil samples were assayed by the proposed process and compared against standard ICP-MS analysis, the results showed good agreement between methods.