A carbon dioxide electrolytic device comprising: a cathode part including a cathode to reduce carbon dioxide and thus produce a carbon compound, a cathode solution flow path to supply a cathode solution to the cathode, and a gas flow path to supply carbon dioxide to the cathode; an anode part including an anode to oxidize water or hydroxide ions and thus produce oxygen and an anode solution flow path to supply an anode solution to the anode; a separator to separate the anode part and the cathode part; a power supply to pass an electric current between the anode and the cathode; a first pressure control unit to control a pressure of the cathode solution flowing in the cathode solution flow path; a second pressure control unit to control a pressure of the carbon dioxide flowing in the gas flow path; a detection unit to detect a production amount of the carbon compound produced by a reduction reaction in the cathode part; and a differential pressure control unit to control a differential pressure between the pressure of the cathode solution and the pressure of the carbon dioxide based on a detection result by the detection unit, so as to adjust the production amount of the carbon compound detected in the detection unit, wherein the anode has a first surface in contact with the separator and a second surface facing the anode solution flow path so that the anode solution is in contact with the anode, wherein the cathode has a first surface facing the cathode solution flow path and a second surface facing the gas flow path, and the cathode solution flow path is disposed between the separator and the cathode so that the cathode solution is in contact with the separator and the cathode, and wherein the cathode has a gas diffusion layer disposed on the second surface side and a catalyst layer disposed on the first surface side and constituted of a cathode catalyst provided on the gas diffusion layer. a cathode part including a cathode to reduce carbon dioxide and thus produce a carbon compound, a cathode solution flow path to supply a cathode solution to the cathode, and a gas flow path to supply carbon dioxide to the cathode; an anode part including an anode to oxidize water or hydroxide ions and thus produce oxygen and an anode solution flow path to supply an anode solution to the anode; a separator to separate the anode part and the cathode part; a power supply to pass an electric current between the anode and the cathode; a first pressure control unit to control a pressure of the cathode solution flowing in the cathode solution flow path; a second pressure control unit to control a pressure of the carbon dioxide flowing in the gas flow path; a detection unit to detect a production amount of the carbon compound produced by a reduction reaction in the cathode part; and a differential pressure control unit to control a differential pressure between the pressure of the cathode solution and the pressure of the carbon dioxide based on a detection result by the detection unit, so as to adjust the production amount of the carbon compound detected in the detection unit, wherein the anode has a first surface in contact with the separator and a second surface facing the anode solution flow path so that the anode solution is in contact with the anode, wherein the cathode has a first surface facing the cathode solution flow path and a second surface facing the gas flow path, and the cathode solution flow path is disposed between the separator and the cathode so that the cathode solution is in contact with the separator and the cathode, and wherein the cathode has a gas diffusion layer disposed on the second surface side and a catalyst layer disposed on the first surface side and constituted of a cathode catalyst provided on the gas diffusion layer.