PROBLEM TO BE SOLVED: To provide an upper arm sphygmomanometer capable of accurately measuring both a blood pressure value and an electrocardiogram waveform. SOLUTION: In a main body (11) of an upper arm sphygmomanometer (10) for measuring a subject's blood pressure using a bag-shaped arm band (51) wrapped around the arm of the subject (100), a main body housing (21) is It has a top surface (22) and left and right first and second side surfaces (25L, 25R), the first side surface has a first side surface electrode region (42L), and the second side surface is a second side surface electrode. A region (42R), the upper surface has a first upper surface electrode region (33L), the first electrocardiogram waveform measurement electrode (43L) is arranged in the first side surface electrode region, and the second electrocardiogram waveform measurement is performed. The electrode (43R) is arranged in the second side surface electrode region, and the first reference electrode (35L) is arranged in the first upper surface electrode region. [Selection diagram] Figure 1【課題】血圧値と心電図波形の両方を正確に測定できる上腕血圧計を提供する。【解決手段】 被験者（１００）の腕に巻き付けられる袋状の腕帯（５１）を用いて被験者の血圧を測定する上腕式血圧計（１０）の本体（１１）において、本体ハウジング（２１）は上面（２２）と左右の第１、２の側面（２５Ｌ、２５Ｒ）を有し、第１の側面は第１の側面電極領域（４２Ｌ）を有し、第２の側面は第２の側面電極領域（４２Ｒ）を有し、上面は第１の上面電極領域（３３Ｌ）を有し、第１の心電図波形測定電極（４３Ｌ）が第１の側面電極領域に配置され、第２の心電図波形測定電極（４３Ｒ）が第２の側面電極領域に配置され、第１の基準電極（３５Ｌ）が第１の上面電極領域に配置されている。【選択図】図１
