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We report the electrochemical hydrogen evolution reaction (HER) of two-dimensional metallic transition metal dichalcogenides (TMDs). <i>TM</i>Te₂ (<i>TM</i>: Mo, W, and V) single crystals were synthesized and characterized by optical microscopy, X-ray diffraction, and electrochemical measurements. We found that <i>TM</i>Te₂ acts as a HER-active catalyst due to the inherent catalytic activity of its basal planes. Among the three metallic <i>TM</i>Te₂, VTe₂ shows the best HER performance with an overpotential of 441 mV and a Tafel slope of 70 mV/dec. It is 668 mV and 137 mV/dec for MoTe₂ and 692 mV and 169 mV/dec for WTe₂. Even though VTe₂ has the lowest values in the exchange current density, the active site density, and turn-over-frequency (TOF) among the three <i>TM</i>Te₂, the lowest charge transfer resistance (R_CT) of VTe₂ seems to be critical to achieving the best HER performance. First-principles calculations revealed that the basal-plane-active HER performance of metallic TMDs can be further enhanced with some Te vacancies. Our study paves the way to further study of the inherent catalytic activity of metallic 2D materials for active hydrogen production.