Novel carbon materials derived from metal‐organic frameworks (MOFs) have attracted much attention, but the commonly inevitable inward contraction during the carbonization process has restricted their structural variety and applications. In this work, a novel rigid‐interface induced outward contraction approach is reported for synthesizing hollow mesoporous carbon nanocubes (HMCNCs) by using ZIF‐8 nanocubes as precursors. HMCNCs exhibit a cubic morphology with the particle sizes slightly larger than ZIF‐8 nanocubes. Due to the unique outward contraction process, uniform carbon nanocubes with a hollow cavity, an outer microporous shell, and an inner mesoporous wall are simultaneously formed with a large pore size (25 nm), high surface area (1085.7 m2 g−1), high porosity (3.77 cm3 g−1), and high nitrogen content (12.2%). When used as a cathode material for Li–SeS2 batteries, the HMCNCs deliver a stable capacity of 812.6 mA h g−1 at 0.2 A g−1 after 100 cycles and an outstanding rate capability (455.1 mA h g−1 at 5.0 A g−1). The findings may pave the way for the construction of distinctive MOF‐derived carbon materials for various applications. Metal‐organic framework (MOF)‐derived hollow mesoporous carbon nanocubes (HMCNCs) with a uniform nanocubic morphology, a large hollow cavity, an outer microporous shell, and an inner mesoporous shell are synthesized via a novel rigid‐interface induced outward contraction approach. When used as a cathode substrate for Li–SeS2 batteries, HMCNCs deliver superior electrochemical performances with stable capacity and outstanding rate capability.