Abstract. Both Conducting and Ferromagnetic polyaniline containing nickel (abbreviated as PANI-Ni) is synthesized in a solution containing aniline, HCl and NiCl2, using peroxydisulphate as an oxidant and horseradish peroxidase as a catalyst. The conductivity of PANI-Ni is about 10 -1 S cm -1 . The result of electron paramagnetic resonance (EPR) spectra indicated that there were unpaired electrons in PANI-Ni, and the spin density of the PANI-Ni was 1.09·10 19 spins g -1 . The plot of magnetization (M) against the magnetic field (H) indicated that the PANI-Ni was soft ferromagnetic at about 300 K, the saturation magnetization (Ms) and the coercive force (Hc) of which were 4.5 emu g -1 (electromagnetic unit per gram) and about 55 Oe, respectively. UV-Visible (UV-vis) and Fourier Transform Infrared (FTIR) spectra showed that there was strong interaction between Ni 2+ and PANI chains, but the backbone chains of PANI-Ni were hardly changed compared with PANI. Cyclic voltammogram results indicated that the PANI-Ni film was of excellent electrochemical activity.