An unmanned aerial vehicle according to various embodiments of the present disclosure comprises: a housing; a wireless communication circuit connected to the housing or positioned in the housing and configured to connect wireless communication with an external controller; a plurality of propulsion systems connected to the housing or at least partially contained in the housing; and a navigation circuit configured to control the plurality of propulsion systems. At least one of the plurality of propulsion systems comprise a motor controlled by the navigation circuit and a propeller assembly connected to the motor. The propeller assembly may comprise: a first structure which is fixed to the motor, which has a cylindrical wall defining an inner space, and which comprises a helical slit formed through the cylindrical wall; a second structure comprising a cylinder portion, at least a part of which is rotatably positioned in the inner space, and at least one protruding portion that protrudes from the outer surface of the cylinder portion to the outside of the cylindrical wall through the helical slit; and a propeller comprising a cylindrical hub engaging with the cylinder portion of the first structure, a plurality of rotating blades extending from the cylindrical hub, and at least one rib extending from the cylindrical hub toward the motor, the propeller being configured such that at least a part of the rib detachably engages with the first structure by the at least one protruding portion of the second structure. Other embodiments are also possible.