Novel hollow nanospheres/cubes of MnCO3 nanostructures have been synthesized successfully by adopting co-precipitation method. Uniform hollow MnCO3 nanospheres/cubes was obtained by controlling the reaction kinetics in the nucleation process of forming manganese carbonates simply by employing NH4HCO3 and NH4SO4 as precipitating agents. Physicochemical and electrochemical performances of the hollow nanospheres/cubes MnCO3 samples are investigated by x-ray diffraction (XRD) scanning electron microscope with energy diffraction x-ray spectroscopy (EDXS), transmission electron microscopy (TEM) and electrochemical techniques. The results show that the hollow nanospheres/cubes of MnCO3 samples have a typical R-3C Rombohedral structure. Especially, the hollow MnCO3 nanosphere sample has excellent super capacitor performance. It delivers a specific capacity of 520 F/g between -0.3 and 0.9 V Vs SCE with capacity retention of 99 % over the 2000 cycles at a current density of 8 A/g at room temperature. Thus, the MnCO3 hollow nanosphere electrode will be a promising energy storage material for advanced supercapacitor applications.