A manufacturing method of a high-precision tension cable net unit of a mesh antenna comprises the following steps that firstly, a moving datum (4) on a linear displacement executing mechanism (2) is adjusted to be zero, and the distance between a fixed datum (3) and the moving datum (4) is calibrated through a theodolite test system; secondly, one end of a tension cable is manufactured to be a first fixed ring, and the fixed datum (3) is sleeved with the first fixed ring; thirdly, after the other end of the tension cable is used as a free end and folded in two, the part, folded in two, of thetension cable is sleeved with a compression connection terminal, and a moving ring is manufactured; fourthly, the moving datum (4) obtained in the first step is sleeved with the moving ring obtained in the third step, the free end of the tension cable is wound around a pretension loading device (6), and then tension is applied; fifthly, the linear displacement executing mechanism (2) is controlledto move, after the linear displacement executing mechanism (2) drives the moving datum (4) to move to a preset position, the compression connection terminal in the third step is tightly pressed, anda second fixed ring is manufactured.