Natural circular dichroism (NCD) provides fundamental insight into molecular chirality and stereochemical environments. Extending this concept into the hard-x-ray regime enables element-specific and site-selective chiral sensitivity inaccessible to optical wavelengths. Here, we demonstrate that $1s2p$ resonant inelastic x-ray scattering (RIXS) can be used to probe NCD in the enantiomeric model compound [Co(en)${}_3]{\left({\mathrm{NO}}_3\right)}_2$. Using high-resolution detection of Co $K\alpha$ emission under circularly polarized excitation at the cobalt $1s$ pre-edge, we observe pronounced dichroic behavior directly linked to the Co-centered chirality. The RIXS-NCD signal reaches $\approx 23\%$ of the pre-edge maximum—more than twice the amplitude of the previously reported x-ray NCD signal for the same compound—and exhibits the expected angular dependence for the crystal's $P{6}_{3}22$ symmetry. Two-dimensional RIXS-NCD maps further reveal strong helicity-dependent features across both excitation and emission energies, providing a richer description of the chiral electronic structure. These results establish RIXS-NCD as a photon-in–photon-out methodology for investigating natural optical activity with elemental and orbital specificity, paving the way for future applications to complex chiral and bioinspired materials.

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• Electronic structure
• Chiral symmetry
• X-ray absorption spectroscopy
• X-ray emission spectroscopy