An acoustic device and an electronic device including the same are provided. The acoustic device and an electronic device include a main body including at least one acoustic output port and at least one air vent port, a speaker unit accommodated in the main body, a first ear tip including at least one first opening area corresponding to the at least one air vent port and detachably coupled to the main body, and a second ear tip including at least one second opening area corresponding to the at least one air vent port and detachably coupled to the main body, wherein one of the first ear tip or the second ear tip may be coupled to the main body so that the main body is worn in a user's ear, and when the first ear tip is mounted, a larger area of the at least one air vent port may be exposed to an external space through the at least one first opening area than when the second ear tip is mounted.