The surface figure precision of lens is decided by the supporting form in lithography objective lens, which influences the performance of optics system further. In order to reach the requirement of lens figure precision, which is better than 5nm RMS, this article introduces a lens supporting structure. The structure includes three points main flexible supporting and six points aided spring supporting. Optimization and analysis to the structure has been done for considering the influence of gravity, clamping force and thermal on figure precision. The conclusion is that PV of upper surface figure is 21.7 nm, RMS is 4.49 nm, PV of lower surface figure is 81.3 nm and RMS is 3.63 nm. The supporting structure satisfies the requirement of high precision figure in lithography objective lens.