Aiming at the problems of high thickness，high cost and difficult support of 2 m grade glass-ceramics mirror，ANSYS finite element analysis software is used to carry out static analysis on the parametric mirror model，and the position and number of support points and layers of Whiffletree 18-point support，27-point support and 36-point support are compared. The relation between the deflection angle of the optical axis and the variation of the surface profile of the mirror is analyzed. According to the results of static analysis，the deflection angle of the 2 m class mirror should not exceed 10°. The support scheme adopts the combination of axial 36-point Whiffletree passive support and lateral 12-point tangential rod A-Frame support. Using this support scheme，the theoretical thickness of the mirror is reduced from 285 mm to 125 mm under the premise that the RMS of the surface type is ≤λ/50（λ=632.8 nm），which greatly reduces the production cost of the mirror and the system weight，indicating that the support structure has good engineering application ability.