An oscillating positive expiratory pressure device comprising a housing enclosing at least one chamber, a chamber inlet configured to receive exhaled air into the at least one chamber, and a chamber outlet configured to permit exhaled air to exit the at least one chamber. A channel is positioned in an exhalation flow path between the chamber inlet and the chamber outlet, with the channel being moveably connected to a chamber of the at least one chamber. An air flow regulator is moveable with respect to the channel between a first position, where the flow of air through the channel is restricted and a second position, where the flow of air through the channel is less restricted, the air flow regulator being configured to repeatedly move between the first position and the second position in response to a flow of exhaled air.