Triclosan is broadly utilized as preservative or antiseptic in various cosmetic and personal care products. It becomes hazardous for environmental safety and human health more than a certain concentration. In this research, graphene oxide (GO) nanosheets were prepared by composing Fe3O4@Au nanostructure decorated GO together with polypyrrole (PPy) (Fe3O4@Au‐PPy/GO nanocomposite) in a facile way. The composite excellent increased the electrochemical response, presenting a high sensitive electrochemical method for triclosan detection. The synthesized Fe3O4@Au‐PPy/GO nanocomposite was characterized for its morphological, magnetically and structural properties by FESEM‐mapping, TEM, and XRD. The Fe3O4@Au‐PPy/GO nanocomposites modified glassy carbon electrodes (GCE), Fe3O4@Au‐PPy/GO GCE, showed a higher sensitivity good stability, reproducibility, lower LOD (2.5×10−9 M) and potential practical application in electrochemical detection of triclosan under optimized experimental conditions. [ABSTRACT FROM AUTHOR]