The invention discloses a support system for a large-sized oblique woven gusset plate lattice shell structure. The support system for the large-sized oblique woven gusset plate lattice shell structure comprises a foundation treatment part, a main support structure mounted on the foundation treatment part and chord positioning steel pipes located on two sides of the main support structure. The assembly method includes the steps of dividing into small units, positioning cross-shaped gusset plates, conducting blanking on the length of a strut angle iron according to coordinate of a positioning coordinate point Z, positioning the strut angle iron to a steel platform, installing the cross-shaped gusset plates to a lattice shell structure, installing lattice shell web members between the cross-shaped gusset plates and the chord positioning steel pipes, and completing the assembly of a woven gusset plate lattice shell unit. By adoption of the novel technical device, the assembly of the woven gusset plate lattice shell can be complete rapidly and accurately, and the support system is convenient and reliable; and high altitude work is reduced greatly, so that safety of construction workers is guaranteed better, and work amount is reduced. According to the support system for the large-sized oblique woven gusset plate lattice shell structure, the application of the assembly method is improved on aspects of cost saving, construction speed, safety and civilized construction.