PROBLEM TO BE SOLVED: To provide a biological sound sensor which hardly peels off from a skin surface of a living body, and in which a member for causing the biological sound sensor to adhere to a skin can be easily replaced.SOLUTION: A biological sound sensor 20a is a biological sound sensor for collecting a biological sound generated in a biological body in a state of being in contact with a skin 11 of a living body and includes: a housing 210 having an opening 230 on a surface 240 on the side that contacts the skin of the living body； a double-sided adhesive film 40, one surface of which adheres to the surface of the housing and closes the opening, and the other surface of which adheres to the skin when collecting the biological sound； and a microphone 220 provided in the housing for collecting the sound. The double-sided adhesive film includes the same material part 430 composed of one kind of material over the full width in the thickness direction, the same material part being composed of an adhesive material having adhesiveness.【課題】生体の皮膚表面からはがれにくく、かつ、皮膚に接着させるための部材を容易に交換可能な生体音センサを提供する。【解決手段】生体音センサ２０ａは、生体の皮膚１１に接触した状態で、生体で発生している生体音の収集を行う生体音センサであって、生体の皮膚に接触する側の面２４０に開口部２３０を有する筐体２１０と、一の面が筐体の面に接着することで開口部を塞ぎ、かつ、他の面が収集のときに皮膚と接着する両面接着膜４０と、筐体内に設けられ、かつ、音を収集するマイクロホン２２０と、を備え、両面接着膜は、厚み方向の全幅にわたって１種類の材料で構成される同一材料部分４３０を有し、同一材料部分は、粘着性を有する粘着性材料で構成されている。【選択図】図６
