Transition metal chalcogenide nanowires could comprise an alternative for nanoelectronics application, yet this class of materials is not well-characterized. Here we predict tunability in I–V characteristics of MoX (X=S, Se) nanowires, dependent on chalcogen atom, Li doping, type of electrode, and morphology. We show an intrinsic negative differential resistance (NDR)-like behavior for Mo6S6 nanowires, explained by bands mismatch in the electronic structure calculated by density functional theory (DFT) within the non-equilibrium Green's function formalism. The NDR-like behavior is suppressed upon Li intercalation or for gold leads. The electron transport results are based on optimized configurations using a non-empirical London dispersion-corrected DFT functional.