A novel FeS/Fe3C nanoparticles encapsulated in porous nitrogen-sulfur dual-doped graphene network (FeS/Fe3C@NS-G) have been successfully fabricated via a one-step in-situ pyrolysis strategy. The nitrogen and sulfur co-doped graphene networks exhibited abundant mesoporous structure and excellent electrical conductivity, facilitating fast electron transport and lithium-ion diffusion. The heterogeneous FeS/Fe3C nanoparticles are homogeneously dispersed in the three-dimensional porous graphene shell with copious internal void space which can accommodate the volume change of the nanoparticles during electrochemical reaction. The FeS/Fe3C@NS-G nanohybrids delivered excellent reversible capacity of 1003 mAh g−1 after 150 cycles at 0.1 A g−1 with a minor capacity decay rate of 1.25%. Furthermore, an ultralong cycling stability of 610 mAh g−1 after 800 cycles at 1 A g−1 with the capacity retention of 91.6% relative to the reversible capacity of the second cycle was observed. This remarkable lithium storage capacity of FeS/Fe3C@NS-G networks reveals their promising potential as anode materials for lithium-ion batteries. Display omitted •FeS/Fe3C nanoparticles in-situ encapsulated in nitrogen-sulfur dual-doped graphene network (NS-G).•NS-G with the abundant internal void space to accommodate the volume change of FeS/Fe3C nanoparticles during cycling.•The 3D interconnected mesoporous graphene network is formed by the addition of glucose.•FeS/Fe3C@NS-G has high-rate long-term cycling stability as Li-ion battery anode.