We present a smart trace metal monitoring system using homemade voltammetric controller and nano electrode array to detect heavy metal ions as Zn, Pb and Cu. The voltammetric controller is featured with smart stage including pre-estimate and optimized measurement. The smart stage can be realized by integrated novel functions such as self-calibration, multi standard solution flow control and automatic deposition time adjustment. Moreover, a mercury-free nano electrode array, consisting gold and platinum electrodes on opposite surface is introduced. Experiments give reliable results of smart trace metal monitoring system. The range of measurement can be expanded as twice as conventional measurements due to smart stage, as well as measurement precision can be improved.