Tubular 0.5Li2MnO3·0.5Li4Mn5O12 has been synthesized by a facile self-templating method starting from tubular β-MnO2. The wall thickness and diameter of 0.5Li2MnO3·0.5Li4Mn5O12 nanotubes are around 200 and 500nm, respectively. X-ray diffraction and transmission electron microscopy observations confirm the composite character, where the Li4Mn5O12 nano-domains are integrated with the Li2MnO3 nano-domains. The tubular composite synthesized at 600°C exhibits better electrochemical properties than that synthesized at 700°C due to the higher ratio of LiMn2O4 decomposed from Li4Mn5O12. The tubular composite also exhibits better electrochemical properties than the microsized aggregated particles due to the unique tubular nanostructure with large specific surface, short Li-ion diffusion pathway, and loose stacking of the tubes.