PROBLEM TO BE SOLVED: To solve the following problem: when a conventional electrocardiogram or heartbeat measurement belt attached to the chest of a subject was tightly wound around the chest, the subject experienced pain in the chest however, when it was not tightly wound around the chest, correct measurement results could not be sometimes obtained because measurement electrodes became out of contact with the chest, for example while the electrodes were in contact with the chest in his/her sleep.SOLUTION: An electrocardiogram or heartbeat measurement device measures an electrocardiogram or heartbeat by bringing conductive plastic electrodes which contains a conductive member, provided on an electrocardiogram or heartbeat measurement belt which is attached to the chest of a subject into contact with the chest of a subject. The device is provided with an attachment belt for attaching the electrocardiogram or heartbeat measurement belt.COPYRIGHT: (C)2015,JPO&INPIT【課題】従来の被測定者の胸部に取り付ける心電または心拍測定ベルトでは胸部にきつく巻くと胸が痛くなり、きつくない力で巻きつけると例えば睡眠中のときに接触しているとき測定用の電極が胸部から接触が解かれ正しい測定結果が得られないことがあった。【解決手段】被測定者の胸部に取り付ける心電または心拍測定ベルトに設けた導電性部材を混入した導電プラスチックを被診断者の胸部に接触させて心電または心拍を測定する心電または心拍測定装置で、その心電または心拍測定ベルトを押える押さえベルトを設ける。【選択図】図8