An electrochemical hydrogen pump includes a hydrogen pump unit including an electrolyte film, an anode catalyst layer, a cathode catalyst layer, an anode gas diffusion layer, an anode separator, a cathode gas diffusion layer, and a cathode separator, a first end plate and a second end plate, a fastener, and a voltage applicator. The electrochemical hydrogen pump transfers and pressurizes hydrogen on the cathode catalyst layer, when a voltage is applied by the voltage applicator. Cathode gas flow channels in which the cathode gas flows are connected to each other. The amount of thickness reduction of the cathode gas diffusion layer due to compression resulting from fastening of the fastener is larger in the hydrogen pump unit positioned at at least one end of the stacked hydrogen pump units than in the hydrogen pump unit positioned at neither end of the stacked hydrogen pump units.