A sound output device according to an embodiment of the present disclosure includes: a speaker configured to generate sound; a guide tube formed in a shape of a hollow tube, the guide tube configured to receive the sound generated from the speaker, through an end of the guide tube, and output the received sound; and a waveguide disposed between the speaker and the guide tube. The waveguide includes: a throat tube configured to connect the speaker and the guide tube to each other, and formed in a shape of a hollow tube, and at least one path change structure configured to adjust a predetermined frequency band of the sound in a process of transmitting the sound generated from the speaker to the guide tube.