Electronic structure and photocatalytic performance of 2D novel Zr₂CO₂/InS heterostructure was systematically investigated using first principle calculations. The calculated results demonstrate that the Zr₂CO₂/InS heterostructure is a direct bandgap semiconductor with a lattice mismatch less than 3% and a formation energy of -0.49 eV, indicating a stable structure. Band gap of the Zr₂CO₂/InS heterostructure is 1.96 eV, which should have a wide visible light absorption range, and the absorption coefficient is up to 10⁵ cm^-1. The heterostructure has a typical type-II band alignment, and its valence band and conduction band offsets are 1.24 and 0.17 eV, respectively, demonstrating the transfer of photo-generated electrons from Zr₂CO₂ layer to InS layer and vice versa for holes, which indicates that the electrons and holes can be separated effectively in space. In addition, InS is an indirect band gap semiconductor material, which can further reduce the recombination of electrons and holes. Therefore, the novel Zr₂CO₂/InS heterostructure is a potential visible-light photocatalyst.