Mercury electrodes have been traditionally used for ASV or potentiometric stripping analysis [13] to obtain high sensitivity, reproducibility, and a wide cathodic potential range. Unfortunately, the toxicity of mercury and its difficulties in handling, storage, and disposal severely restrict its use as an electrode material. Recently, the bismuth film electrode was introduced for the electrochemical measurements of heavy metals because it possesses behavior similar to the mercury electrode and it is more environmentally friendly [14]. The bismuth (Bi) can be constructed by electrodeposition on substrates including glassy carbon [15], screen-printed carbon ink (SPCE) [16]. Carbon nanotubes (CNTs) have been proven to possess potential for heavy metals analysis due to their high electrical conductivity, high surface area, significant mechanical strength, and good chemical stability. Therefore, the fabrication of screen-printed carbon nanotubes electrode (SPCNTE) is attractive. In effort to improve the sensitivity of heavy metals by electrochemical analysis, Bi-SPCNTE was used as the working electrode [17,18] in batch analysis.