Recent studies have focused on the relationship between charge density wave (CDW) collective electronic ground states and nontrivial topological states. ${\mathrm{YTe}}_3$, a nonmagnetic quasi-two-dimensional chalcogenide, has been reported to exhibit a CDW state below 334 K. Using angle-resolved photoemission spectroscopy (ARPES) and density functional theory (DFT), we establish that ${\mathrm{YTe}}_3$ is a CDW-induced Kramers nodal line (KNL) metal, a recently proposed topological state of matter. Scanning tunneling microscopy and low energy electron diffraction reveal two orthogonal domains, each with a unidirectional CDW and a similar wave vector (${\mathbf{q}}_{{}_{\mathrm{CDW}}}$). When the influence of twin domains is considered, the effective band structure (EBS) computations that utilize DFT-calculated bands using a noncentrosymmetric structure determined by x-ray crystallography, show excellent agreement with ARPES. The noncentrosymmetry of ${\mathrm{YTe}}_3$ is established by Raman spectroscopy. The Fermi surface and ARPES intensity plots show weak shadow bands displaced by ${\mathbf{q}}_{{}_{\mathrm{CDW}}}$ from the main bands. These are linked to CDW modulation, as the EBS calculation confirms. Bilayer split main and shadow bands suggest the existence of crossings, according to theory and experiment. DFT bands, including spin-orbit coupling, indicate existence of a KNL along the $\mathrm{\Sigma }$ direction from multiple crossings of bands dispersing perpendicular to it. Additionally, doubly degenerate bands are only found along the KNL at all energies, with some bands dispersing through the Fermi level.

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• Charge density waves
• Fermi surface
• Spin-orbit coupling
• Symmetry protected topological states
• Chalcogenides
• Layered crystals
• Nodal-line semimetals
• Two-dimensional electron system
• Angle-resolved photoemission spectroscopy
• Crystallography
• Density functional theory
• Scanning tunneling microscopy