To provide a loudspeaker, where mechanical strength is high at a drive section, a risk such as burnout by heat generation and breakdown, is canceled, and a sound tube is provided on a sounding side.

The loudspeaker 10 has the sound tube 15 provided on the sounding side, a casing 11, an ultra magnetostrictive member 12, and a magnetic field generation section 14. The casing has a phase equalizer 16 arranged in the sound tube. The ultra magnetostrictive member is arranged in the casing, is displaced according to variation in a magnetic field, and directly oscillates air by the displacement edge. The magnetic field generation section is arranged around the ultra magnetostrictive member at an interval and generates the magnetic field according to the supply of a drive current based on a sound signal. When the drive current based on the sound signal is supplied to the magnetic field generation section, the magnetic generation section generates the magnetic field. The generated magnetic field is given to the ultra magnetostrictive member, and the ultra magnetostrictive member is extended based on the field, to become the drive section for oscillation.