An unmanned aerial vehicle comprising: a plurality of arm units (200a-d), each of the plurality of arm units (200a-d) comprising a rotary wing, a motor, and an arm main body and detachably coupled to a main body of the unmanned aerial vehicle; the main body of the unmanned aerial vehicle comprising a plurality of receptacles for coupling to the plurality of arm units (200a-d); and a battery unit coupled to the main body of the unmanned aerial vehicle to be exposed to outside wherein at least a part of the battery unit is exposed to outside when the battery unit is coupled to the main body of the unmanned aerial vehicle, wherein the battery unit is detachably coupled to the main body of the unmanned aerial vehicle, and wherein the battery unit comprises a battery and a battery case accommodating the battery, and wherein the unmanned aerial vehicle further comprises a clamping structure to detachably clamp the main body of the unmanned aerial vehicle and the battery unit to each other; characterized in that the main body of the unmanned aerial vehicle comprises a lower frame; wherein a main control member is firmly installed on an upper portion of lower frame, and the main control member is configured to receive a signal transmitted from an external controlling device and controlling the unmanned aerial vehicle; and wherein each of the plurality of arm units (200a-d) comprises a motor control member in the arm main body configured to receive a control signal from the main control member and to control a speed of the motor, the arm units (200a-d) configured to be detachable from the main control member, and wherein the receptacles are provided at edge parts of the main control member, and wherein the arm main body comprises a plug terminal adapted to be inserted into each of the receptacles of the main control member; and an arm lower cover having a connector installed thereon and adapted to transceive a signal with respect to the main body of the unmanned aerial vehicle and to transfer the signal to the motor control member. a plurality of arm units (200a-d), each of the plurality of arm units (200a-d) comprising a rotary wing, a motor, and an arm main body and detachably coupled to a main body of the unmanned aerial vehicle; the main body of the unmanned aerial vehicle comprising a plurality of receptacles for coupling to the plurality of arm units (200a-d); and a battery unit coupled to the main body of the unmanned aerial vehicle to be exposed to outside wherein at least a part of the battery unit is exposed to outside when the battery unit is coupled to the main body of the unmanned aerial vehicle, wherein the battery unit is detachably coupled to the main body of the unmanned aerial vehicle, and wherein the battery unit comprises a battery and a battery case accommodating the battery, and wherein the unmanned aerial vehicle further comprises a clamping structure to detachably clamp the main body of the unmanned aerial vehicle and the battery unit to each other; characterized in that the main body of the unmanned aerial vehicle comprises a lower frame; wherein a main control member is firmly installed on an upper portion of lower frame, and the main control member is configured to receive a signal transmitted from an external controlling device and controlling the unmanned aerial vehicle; and wherein each of the plurality of arm units (200a-d) comprises a motor control member in the arm main body configured to receive a control signal from the main control member and to control a speed of the motor, the arm units (200a-d) configured to be detachable from the main control member, and wherein the receptacles are provided at edge parts of the main control member, and wherein the arm main body comprises a plug terminal adapted to be inserted into each of the receptacles of the main control member; and an arm lower cover having a connector installed thereon and adapted to transceive a signal with respect to the main body of the unmanned aerial vehicle and to transfer the signal to the motor control member.