Polypyrrole (PPy) composites were prepared with both unmodified and amine-modified multiwalled carbon nanotubes (MWCNTs) in the presence and absence of barium titanate (BaTiO3) by in situ oxidative polymerization. A uniform coating of PPy on the MWCNTs and BaTiO3 surfaces was confirmed by field emission scanning electron microscopy and high-resolution transmission electron microscopy images. The structure of the pure and amine-modified MWCNTs were identified by Fourier transform infrared spectroscopy. The incorporation of BaTiO3 enhanced the thermal stability and capacitance properties of the composites. The maximum specific capacitance and energy density values found for the PPy/amine-modified MWCNT/BaTiO3 composites were 155.5 F/g and 21.6 W h/kg, respectively, at a scan rate of 10 mV/s. The maximum power density was found to be 385.7 W/kg for the same composite at a scan rate of 200 mV/s. Furthermore, the impedance spectra of the composites showed moderate capacitive behavior. (C) 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 128: 698-705, 2013