The invention discloses a high-pressure hydrogen gas supply device, which comprises a closed hydrogen storage chemical bed filled with an LaNi5 material, an outlet pipeline connected with an inner space of the hydrogen storage chemical bed, a first high pressure valve and a pressure sensor which are arranged on the output pipeline, a heater arranged by wrapping the hydrogen storage chemical bed, and a temperature controller connected with the heater. The hydrogen is stored by adopting a solid hydrogen storage material, a large and bulky steel cylinder for storing high-pressure hydrogen gas is not needed, and the extremely low temperature conditions for the storage of liquid hydrogen are not needed; when the hydrogen needs to be stored, an alloy is reacted with hydrogen to produce a metal hydride and heat is released; when the hydrogen needs to be used, the hydrogen stored in the solid hydrogen storage material is released by heating or decompression.