The invention provides an LTD module with a novel structure and a trigger method of the LTD module. Only one path of trigger pulses needs to be led in the module of each level of an LTD, and a branch arranged inside the LTD module and an angular transmission line arranged on an insulator in the middle of the LTD module are used for achieving synchronous triggering of switches of the other branches of the LTD module. The trigger mode of the LTD module is not limited by the factors of the secondary coupling overvoltage trigger mode, wherein the factors comprise the factor of the coupling time response characteristic of a magnetic core in ultrafast leading-edge pulses, the factor that whether the breakdown closing time of the branch switches under the condition of direct-current superposition secondary coupling voltage is smaller than the transmission time of an electric pulse on the secondary grade of the LTD, and the factor that whether insulation of an induction cavity can meet the requirements, and the LTD module and the trigger method of the LTD module have better technical feasibility.