© 2020 Elsevier B.V.A polyacrylonitrile/polyindole (PAN/PIN) [50, 50] conducting polymer composite was chemically synthesized using FeCl3 as an oxidizing agent in chloroform solution and nitrogen atmosphere at 10 °C. The formation of the composite was supported by Fourier transform infrared spectroscopy. The morphological properties of the composite were investigated by atomic force microscopy and scanning electron microscopy. The thermal properties of the composite were examined by using thermogravimetric analyses. It was found that the composite had good thermal stability. The conducting polymer composite was used for the first time as an adsorbent for solid phase extraction of Cu (II). The optimum pH was found to be 7. The adsorption and elution shaking times were 5 and 15 min, respectively. The elution was done with 5 mL of 2 mol L−1 HNO3. The accuracy of the developed method was confirmed by analyzing certified reference material (TMDA-70.2 Lake Water).