Porous nano-MnO2 decorated bamboo-based activated carbon was fabricated by an in situ preparation method. MnO2 with size of about 16.92 nm is uniformly loaded on the surface of bamboo-based activated carbon. Such unique bamboo-based activated carbon @ MnO2 nanocomposites exhibited excellent electrochemical performance: a high specific capacitance of 221.45 F g(-1) at the current density of 1 A g(-1), an excellent rate capability and a good cycling performance with 89.29% retention after 1000 cycles at the current density of 1 A g(-1). The results indicate that this kind of hybrid core-shell bamboo-based activated carbon @ MnO2 nanocomposites have great potential in future practical applications.