An ultrasonic transducer (1) includes a substrate (2), a supporting film (5), and a piezoelectric element (7). The substrate (2) includes an opening (21). The supporting film (5) is configured on the substrate (2) to cover the opening (21). The piezoelectric element (7) is configured at a part of the supporting film (5). The part overlaps with the opening (21) in a planar view in a thickness direction of the substrate (2). A thickness of the part of at a center of gravity in the planar view is smaller than a thickness of an outer edge portion of the part. The outer edge portion is closer to the substrate (2) than the center to the substrate (2).
