To inhibit complication of an air frame structure, reduce a workload of flight preparation, and improve portability and space efficiency of an unmanned aircraft.SOLUTION: An unmanned aircraft includes: first arms and second arms, each forming a pair of arm members; a rotor supported by these arms; a fuselage to which these arms are connected; and fixtures each of which fixes a relative arrangement angle of these arms. Each of these arms can revolve around a connection part of the arm connected to the fuselage in a direction in which these arms can move close to/away from each other. The first arm has a positioning piece that is a protruding part protruding to the second arm side. The positioning piece contacts with an outer surface of the second arm by moving the first arm and the second arm close to each other. The fixture fixes the positioning piece and the second arm in an undetachable manner in a state where the positioning piece contacts with the second arm. The above problem is solved by the unmanned aircraft.SELECTED DRAWING: Figure 2