Herein a conspicuously simple and sensitive electrochemical sensor based on nanocomposite architecture of the one-pot synthesized carbon nanodots (CNDs) and chitosan (CS) composite film was proposed for the determination of triclosan. The electrochemical response of triclosan was examined, demonstrated the irreversible electrochemical oxidation and one electron involved process of triclosan. Due to the good conductivity, large surface area and excellent electrochemical activity of CNDs, the CS and CNDs hybrid film extremely amplified the electrochemical response of triclosan, offering a highly sensitive electrochemical platform for triclosan detection. The detection limit of this electrochemical sensor for triclosan could be down to 9.2 nM. The as-proposed sensor presented high sensitivity, low detection limit, wide dynamic response range, excellent stability and reproducibility. This simple and sensitive electrochemical sensor is promising in developing the disposable sensor for environmental monitoring and food inspection. (C) 2012 Published by Elsevier Ltd.