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. <EOS>