A MoS2-based nanocomposite for use as an anode in lithium-ion batteries was prepared via a facile and scalable high-energy mechanical milling (HEMM) technique. In this study, we report the effect of the type of carbon matrix (2D graphite (G), 1D carbon nanotube (CNT), and 0D amorphous carbon (C)) as well as that of the HEMM time on the electrochemical performances. Among all nanocomposites studied, MoS2/G exhibited the most excellent cycle life, delivering a gravimetric capacity of 737 mAh g−1 after 210 cycles (84% retention) and outstanding rate performance, resulted from a homogenous mixing between MoS2 and G. In addition, as compared to MoS2/CNT and MoS2/C, the capacity retention of MoS2/G over long-term cycling was markedly steady and stable for various milling times applied. Furthermore, the best weight ratio between MoS2 and G was experimentally determined to be 7:3 based on the electrochemical performances. The superiority of MoS2/G was further investigated by density functional theory calculations, which showed the much higher binding energy of G than CNT toward MoS2, leading to the improved miscibility and the mechanical robustness of MoS2/G. Overall, the MoS2/G nanocomposite synthesized by a simple HEMM process presents a new and promising candidate for high-performance anodes for LIBs.