Abstract: An open-ear earphone includes a housing, a chamber is provided inside the housing, a speaker is provided inside the chamber and divides the chamber into a front chamber and a rear chamber. The housing is provided with a first sound hole and a second sound hole. The front chamber is communicated to the outside through the first sound hole, and the rear chamber is communicated to the outside through the second sound hole. The rear chamber includes a first volume down chamber and a second volume down chamber communicated to the first volume down chamber, and the first volume down chamber is located between the speaker and the second volume down chamber. The sound wave in backward motion generated by the speaker is transmitted to the outside from the second sound hole after being reduced by the first volume down chamber and the second volume down chamber.