A three-electrode-system-type electrode potential measurement device configured to measure an electrode potential of a cylindrical battery cell in a state in which a beading portion provided between a top cap assembly, at which a first electrode terminal of the cylindrical battery cell is located, and a battery case, at which a second electrode terminal of the cylindrical battery cell is located, is divided, the electrode potential measurement device comprising: a working electrode connection unit connected to the first electrode terminal or the second electrode terminal configured to measure an electrode potential of the first electrode terminal or the second electrode terminal; a counter electrode connection unit connected to the electrode terminal that is not connected to the working electrode connection unit; a reference electrode connection unit connected to a reference electrode, which forms a battery circuit for electrode potential measurement, configured to measure a relative value of the potential of the electrode terminal connected to the working electrode connection unit; a measurement unit connected to the working electrode connection unit, the counter electrode connection unit, and the reference electrode connection unit configured to measure the potential of the electrode connected to the working electrode connection unit; and a short-circuit prevention member located between the top cap assembly and the battery case, between which the beading portion is divided, in a state of being in contact with the top cap assembly and the battery case configured to prevent occurrence of a short circuit due to contact between the top cap assembly and the battery case of the cylindrical battery cell, wherein the cylindrical battery cell in the divided state and the reference electrode are soaked in an electrolytic solution contained in a tray. a working electrode connection unit connected to the first electrode terminal or the second electrode terminal configured to measure an electrode potential of the first electrode terminal or the second electrode terminal; a counter electrode connection unit connected to the electrode terminal that is not connected to the working electrode connection unit; a reference electrode connection unit connected to a reference electrode, which forms a battery circuit for electrode potential measurement, configured to measure a relative value of the potential of the electrode terminal connected to the working electrode connection unit; a measurement unit connected to the working electrode connection unit, the counter electrode connection unit, and the reference electrode connection unit configured to measure the potential of the electrode connected to the working electrode connection unit; and a short-circuit prevention member located between the top cap assembly and the battery case, between which the beading portion is divided, in a state of being in contact with the top cap assembly and the battery case configured to prevent occurrence of a short circuit due to contact between the top cap assembly and the battery case of the cylindrical battery cell, wherein the cylindrical battery cell in the divided state and the reference electrode are soaked in an electrolytic solution contained in a tray. <EOS>