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Lead or cadmium is one of the most serious environmental pollutants, which are highly toxic to human nervous, immune, reproductive and gastrointestinal systems.Rice is one of the world major food crops and more than 3 billion people take it as their staple diet.However, rice is very susceptible to heavy metals pollutants, because its growth process requires a lot of irrigation water, which may be polluted by raw sewage effluent and untreated industrial wastewater.The contents of heavy metal ions are usually detected by several spectrometric methods, including inductively-coupled mass spectrometry (ICP-MS), high performance liquid chromatography (HPLC) and Flame atomic absorption spectrometry (FAAS).These methods, however, require expensive instrument, toxic organic solvents, time consuming, complex operation and sometimes lack in sensitivity.In comparison, Electrochemical methods, especially electrochemical stripping analysis, have been widely recognized as a powerful tool for determination of heavy metals due to its low cost, easy operation, high sensitivity and selectivity.In this work, a bismuth film/poly(p-aminobenzene sulfonic acid)/ hydroxyl multi-wall carbon nanotubes/ ionic liquid composite modified electrode was prepared and manufactured by using electrodeposition of hydroxyl multi-wall carbon nanotubes, ionic liquid, electropolymerization of p-ABSA, and in situ plating bismuth film methods, successively.The fabricated electrode was further applied to detect trace of cadmium ions by SWASV.Some physical and electrochemical methods such as scanning electron microscope (SEM) cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and linear sweep voltammetry (LWV) were further applied to investigate the properties of this electrode.It was found that the formed hydroxyl multi-wall carbon nanotubes/ionic liquid layer on the top of GCE could remarkably facilitate the electron transfer and enlarge the specific surface area of the electrode.While the poly(p-ABSA) film could effectively increase the adhesion and stability of hydroxyl multi-wall carbon nanotubes/ionic liquid layer, enhance ion-exchange capacity and prevent the macromolecule in real samples absorbing on the surface of electrode.By combining co-deposits ability with heavy metals of bismuth film, the obtained electrode exhibited a good stripping performance for the analysis of Cd (Ⅱ) and Pb (Ⅱ).Under the optimum conditions,the linear range of electrode was from 1.0 to 80.0 μg L-1 for both metal ions with a detection limit of 0.08 μg L-1 for cadmium and 0.10 μg L-1 for lead (S/N =3).Finally, the proposed analytical procedure was applied to detect trace metal ions in real samples with satisfactory results.