An unusual CC⋯CO interaction has been discovered in (Z)-3-[(4-halogenphenyl)amino]-2-cyanoprop-2-enoates and rationalized by the density functional theory calculations. Second order perturbation theory analysis based on the NBO method and LMOEDA energy decomposition further reveals that the CC⋯CO interaction is mainly dominated by dispersion and electrostatic energies, and two orbital interactions.