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Isomorphic titanium dichalcogenides TiX2 (X = S, Se, Te) exhibit diverse and anisotropic chemical and physical properties. Bulk TiSe2 was found to exhibit anomalous behavior at low temperatures, leading to emergence of a charge density wave (CDW) due to superstructure formation, bulk TiS2 and TiTe2 do not exhibit CDW instability. The diversity is investigated through the electronic structure by using density functional theory‐based full potential linearized augmented plane wave and projector augmented wave methods. The latest generalized gradient approximation‐Perdew–Burke–Ernzerhof correction for solids–Trans‐Blaha‐modified Becke–Johnson potential confirm that TiS2 is semiconducting whereas TiSe2 and TiTe2 are metallic. The diverse properties are governed by two bands, S/Se/Te p‐band near the Γ‐point and Ti 3d‐band around M (L)‐points. The phonon and energy band structures are correlated to explain the occurrence of CDW. Phonon mode with imaginary frequency indicates lattice instability and the displacements of Ti—Se atoms allows the mixing of states of the electron and hole pockets leading to lattice distortion, which lowers the energy of the TiSe2 system.

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