In this study, ternary composites of polyaniline (PANI) with manganese dioxide (MnO) nanorods and carbon nanotubes (CNTs) were prepared by employing a hydrothermal methodology and in-situ oxidative polymerization of aniline. The morphological analysis by scanning electron microscopy showed that the MnO possessed nanorod like structures in its pristine form, while in the ternary PANI@CNT/MnO composite, coating of PANI over CNT/MnO, rods/tubes were evidently seen. The structural analysis by X-ray diffraction and X-ray photoelectron spectroscopy showed peaks corresponding to MnO, PANI and CNT, which suggested efficacy of the synthesis methodology. The electrochemical performance in contrast to individual components revealed the enhanced performance of PANI@CNT/MnO composite due to the synergistic/additional effect of PANI, CNT and MnO compared to pure MnO, PANI and PANI@CNT. The PANI@CNT/MnO ternary composite exhibited an excellent specific capacity of 143.26 C g at a scan rate of 3 mV s. The cyclic stability of the supercapattery (PANI@CNT/MnO/activated carbon)-consisting of a battery type electrode-demonstrated a gradual increase in specific capacity with continuous charge-discharge over ~1000 cycles and showed a cyclic stability of 119% compared to its initial value after 3500 cycles.