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In this work, hierarchical hexagonal nanoplates NiO composite with microcrystalline graphite are successfully synthesized by a hydrothermal process. Carbon nanofibers are disaggregated to the microcrystalline graphite and they are dispersed in NiO hexagonal structure (H–NiO sample). Microcrystalline graphite (1 wt% of the composite) has effect on growth NiO hexagonal nanoplates, improving the sample conductivity and stability. At the first cycle, H–NiO sample presents a high discharge capacity of 1357.2 mAh g−1 and a charge capacity of 1002.6 mAh g−1 with an initial coulombic efficiency of 73.9%. After 45 cycles, H–NiO sample exhibits a high reversible capacity of 1111.6 mAh g−1. The lithium diffusion coefficient of the H–NiO is calculated to be 7.517 × 10−12 cm2 s−1 with faster Li+ diffusion ability than pure NiO sample. The microcrystalline graphite in the composite electrode can effectively decrease the volume change and pulverization of NiO component, meanwhile, it hinders the aggregation in the cycled electrode. The microcrystalline graphite with intrinsic stability has potential application in producing composites with other metal oxides for highly reversible lithium storage capability. The as-produced microcrystalline graphite is in-situ composite with NiO hexagonal plates and play the key role in enhancement of electrochemical properties. The H–NiO nanoplates which is supported by microcrystalline graphite exhibits an excellent cycling stability, with a high reversible capacity of 1111.6 mAh g−1 at a current density of 100 mA g−1 after 45 cycles. Image 1 • Hierarchical hexagonal nanoplates NiO with microcrystalline graphite is synthesized. • Carbon nanofibers disaggregated to microcrystalline graphite and composite with NiO. • Microcrystalline graphite plays the key role in enhanced electrochemical properties. • H–NiO nanoplates presents discharge/charge capacities of 1357.2/1002.6 mAh g−1. • H–NiO exhibit reversible capacity of 1111.6 mAh g−1 after 45 cycles. [ABSTRACT FROM AUTHOR]