The invention provides a swing arm type six-DOF (Degree of Freedom) mechanism, which is provided with a base frame and a movable platform rigid body which is connected with the base frame; the connecting way of the base frame and the movable platform rigid body is as follows: the frame is provided with three telescopic columns which are vertical to the plane of the frame; the three telescopic columns are respectively fixed on three vertexes of an equilateral triangle which is arranged on the frame; each telescopic column is provided with a telescopic swing arm; each telescopic swing arm is vertical to the telescopic column; on end of each telescopic swing arm is fixedly connected with the top end of the telescopic column respectively so as to form a cantilever beam; the other end of each telescopic swing arm is fixedly connected on three vertexes of the equilateral triangle on the movable platform by a ball pivot. The swing arm type six-DOF mechanism realizes the axial supporting and the radial supporting of the supported article simultaneously; the temperature deformation and stress can be eliminated by the swinging of the swing arm; the coupling degree of components is small, thus being beneficial for the motion control; the movable platform and the base frame plane are allowed to have a common surface and be mutually passed through; the swing arm type six-DOF mechanism is applicable for the sites where the space height is small and the displacement and self-rotation range are large.