The invention discloses a construction method for forming a spherical-rib annular cable dome structure by stretching a ridge cable once. The method comprises the following steps of: firstly, connecting the ridge cable with an upper end node of each vertical pressure lever respectively, placing the lower part of each vertical pressure lever on a temporary scaffold respectively, and raising the top of each vertical pressure lever to a construction standard height which is calculated by a method provided by the invention; secondly, connecting one end of a central oblique cord to the ridge cable, and connecting the other end of the central oblique cord to the lower end of a central vertical pressure level; thirdly, connecting an annular cable with the lower ends of the vertical pressure levers turn by turn from inside to outside, connecting one end of the oblique cord with the ridge cable, and connecting the other end of the oblique cord with the lower ends of the vertical pressure levers and the annular cable; and finally, stretching the cable end part of the ridge cable at a ring beam, and anchoring the ridge cable on the pressed ring beam when the cable end part of the ridge cable is stretched to reach a designed position. The construction method for the cable dome structure only needs to stretch and draw the ridge cable once, and the cable dome structure can be mounted according to numerical values in a table provided by the invention, so that the extremely-complex structure in the conventional construction technique is possible to be generally popularized.