An ultrasound probe includes: a transducer unit having a plurality of ultrasound transducers； a flexible substrate 72 configured to be flat L-shaped in a relaxed state； and a plurality of coaxial wires that electrically connects the transducer unit to the flexible substrate 72. A plurality of signal lines 721S electrically connected to the transducer unit via the plurality of coaxial wires and a first return GND 721G1 that serves as a ground for the plurality of signal lines 721S are formed on the flexible substrate 72. The first return GND 721G1 is formed on an inner part 72I of the L-shaped flexible substrate 72 with respect to the plurality of signal lines 721S.
