The photoelectric pulse wave sensor (2) has a light emitting element (21) and a light receiving element (22) arranged on the main surface of the wiring board (30) at a predetermined interval, and a wiring board (30) attached thereto, and emits light. A pair of openings (104, 105) are formed in association with each of the element (21) and the light receiving element (22), and at least a light-shielding part (104) provided between the pair of openings (104, 105). 101). The light shielding portion (101) is provided on the surface of the housing (10) facing the wiring board (30), has light shielding properties and flexibility, and the wiring board (30) is attached to the housing (10). A light-shielding member (102) that deforms in contact with the wiring board (30).光電脈波センサ（２）は、配線基板（３０）の主面に所定の間隔を空けて配置される発光素子（２１）及び受光素子（２２）と、配線基板（３０）が取付けられ、発光素子（２１）及び受光素子（２２）それぞれに対応付けて一対の開口部（１０４，１０５）が形成されるとともに、少なくとも当該一対の開口部（１０４，１０５）の間に設けられた遮光部（１０１）を有する筐体（１０）とを備える。遮光部（１０１）は、筐体（１０）の配線基板（３０）と対向する面に設けられ、遮光性及び可撓性を有し、配線基板（３０）が筐体（１０）に取り付けられたときに配線基板（３０）と当接して変形する遮光部材（１０２）を含む。
