An earphone, comprising: a housing that includes a chamber; wherein a sound guiding portion is disposed on a side face of the housing, a speaker unit is arranged in the chamber of the housing and has a sound outputting portion oriented towards the sound guiding portion, and a sound guiding tube is disposed in the sound guiding portion and connected to an inner wall of the sound guiding portion via a connecting portion, wherein an inner sound guiding channel is located in the sound guiding tube; wherein: the inner sound guiding channel and an outer sound guiding channel are formed in the sound guiding portion and the outer sound guiding channel is located between the sound guiding portion and the sound guiding tube; wherein the inner sound guiding channel, at a frond end thereof, opens at one sound output hole and the outer sound guiding channel, at an end face of the sound guiding portion that is located away from the housing, opens at a sound output hole, and the sound output of all the sound output holes (15A, 18A) is directed toward the direction that the sound guiding portion extends; wherein the front end of the sound guiding tube protrudes from the end face of the sound guiding portion such that the sound output hole of the inner sound guiding channel is farther from the housing than the sound output hole of the outer sound guiding channel, in the direction that the sound guiding portion extends; and an ear plug sleeve is sleeved on the sound guiding portion, the ear plug sleeve being an elastic rubber body and having one opening corresponding to the the sound output hole of the outer sound guiding channel, whereby the sound waves generated by the sound outputting portion of the speaker unit are transmitted to the inside of the ear of the user through the sound guiding portion, the sound waves in the inner sound guiding channel directly passing through the sound output hole of the inner sound guiding channel, the sound waves in the outer sound guiding channel directly passing through the sound output hole of the outer sound guiding channel. the inner sound guiding channel and an outer sound guiding channel are formed in the sound guiding portion and the outer sound guiding channel is located between the sound guiding portion and the sound guiding tube; wherein the inner sound guiding channel, at a frond end thereof, opens at one sound output hole and the outer sound guiding channel, at an end face of the sound guiding portion that is located away from the housing, opens at a sound output hole, and the sound output of all the sound output holes (15A, 18A) is directed toward the direction that the sound guiding portion extends; wherein the front end of the sound guiding tube protrudes from the end face of the sound guiding portion such that the sound output hole of the inner sound guiding channel is farther from the housing than the sound output hole of the outer sound guiding channel, in the direction that the sound guiding portion extends; and an ear plug sleeve is sleeved on the sound guiding portion, the ear plug sleeve being an elastic rubber body and having one opening corresponding to the the sound output hole of the outer sound guiding channel, whereby the sound waves generated by the sound outputting portion of the speaker unit are transmitted to the inside of the ear of the user through the sound guiding portion, the sound waves in the inner sound guiding channel directly passing through the sound output hole of the inner sound guiding channel, the sound waves in the outer sound guiding channel directly passing through the sound output hole of the outer sound guiding channel.