This paper aims to present the topological structure design and kinematic analysis of a novel double-ring truss deployable satellite antenna mechanism. First, a new topological scheme and a new rectangular prism deployable linkage unit are proposed for constructing the kind of antenna mechanisms. Second, the degree-of-freedom (DOF) of the deployable unit and the antenna mechanism are analyzed based on structure decomposition and screw theory. Third, the kinematic model of the double-ring truss deployable antenna mechanism is established based on its structural characteristics. Finally, a typical numerical example is used to illustrate the effectiveness of the designed mechanism and the established kinematic model. The new double-ring truss deployable antenna mechanism consists of the units with the better structural symmetry and has simpler joint axis layouts, comparing with the same type of most existing mechanisms.