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A detection system for rapid monitoring heavy metals in soil based on electrochemical and virtual instrument technology was developed. The ultrasonic-assistant extraction technique was used for rapid pretreatment of soil samples. Single use sensors bismuth film modified screen-printed electrodes coupled with differential pulse anodic stripping voltammetry (DPASV) provided a rapid, accurate screening system for the simultaneous determination of cadmium and lead in soil. The control program, developed in LabView, was adopted as control kernel, by combining the MSP430 microcontroller, the potentiostat circuit, I/V conversion circuit, peristaltic pump and electromagnetic valve. This system realized the automatic measurement. The probability statistics algorithms and the standard addition method were employed to overcome the inherent measurement errors existed in real soil analysis and the system detection limits were 1.8μg/L for cadmium and 2.6μg/L for lead, respectively. Experimental results showed that the system possesses many advantages such as high precision, good reproducibility, high speed and low power consumption, which was suitable for rapid evaluation and measurement of heavy metals in soil.