The invention provides an assembly-line automatic manufacturing technology for a pre-stressed concrete track board unit by a pre-tensioning method. Traction equipment drives a model to flow on a track according to a time beat, wherein the time beat is working time of each station; the model bears tensioning stress, and all the stations are lined up on an assembly line and work together at the same time; and the quality and the working progress of each station are controlled by a sensor, and each station is commanded by a central control system, so that the operation of the whole system is controlled. Compared with a matrix production method, the assembly-line automatic manufacturing technology has the advantages that temporary components such as a tensile pedestal are eliminated, the model turnover rate is increased by 50 percent, the area of a factory is reduced by 30 percent or above, and the number of workers is reduced by 50 percent or above. The production process fulfills the aims of full-automatic control, informationalized transmission of key data, remote monitoring, and relocation and quick installation of all sets of equipment according to engineering requirements.