An electrochemical reaction device comprises; an anode to oxidize water and thus generate oxygen; an electrolytic solution flow path facing on the anode and through which a first electrolytic solution containing the water flows; a a cathode to reduce carbon dioxide and thus generate a carbon compound; a separator between the anode and the cathode; a power supply connected to the anode and the cathode; and a flow path plate including a first flow path facing on the cathode and through which the carbon dioxide flows and a second flow path facing on the cathode and through which at least one of a second electrolytic solution and the carbon dioxide flows.