Novel materials and structures with abundant active sites have been in continuous demand for electrochemical catalytic applications. In this study, we synthesized platinum telluride (Pt3Te4) nanocrystals on two-dimensional metallic molybdenum ditelluride (MoTe2) using a dynamic hydrogen bubble template method in the hydrogen evolution reaction (HER). The local crystal structure and chemical state of the Pt3Te4 nanocrystals were investigated using X-ray nano-diffraction and X-ray nano-absorption spectroscopy. In our electrochemical deposition method, the morphology, and HER performance of the Pt3Te4 nanocrystals could be manipulated through the hydrogen bubble generation rate. Thus, the nanorod-shaped Pt3Te4 nanocrystals, fabricated by a high rate of hydrogen bubble generation, exhibited outstanding HER performance, which is in contrast with the HER performance of hemisphere-shaped Pt3Te4. Our study provides a facile and systematic way of synthesizing high-performance electrochemical catalysts using the hydrogen bubble-assisted growth method.