A sensor module includes a first member including a first recess in which a piezoelectric element including an electrode is arranged, a second member joined to the first member, a first plate in contact with the second member, a second plate in contact with the first member, and a fastening section configured to fasten the first plate and the second plate. A first projection projecting toward the second member is provided on the first plate. The internal height of the first recess of the first member is larger than the height of the piezoelectric element. The piezoelectric element is in contact with the second member.