A vacuum drying system includes: a support platform, which is used to support the substrate, wherein the support platform comprises a plurality of sub-platforms which are arranged along a predetermined direction and there are gaps between the adjacent sub-platforms; a mechanical arm which comprises a plurality of strip structures at positions corresponding to the gaps, and is used to place the substrate onto the support platform or move the substrate out of the support platform. Comparing to the prior art wherein the substrate is supported by a plurality of needle-shaped supports in the vacuum drying process, in the technical solution of the present disclosure, the contact area between the support platform and the substrate is much larger, which can reduce the local pressure on the substrate, thereby avoiding the display brightness mura of the substrate caused by the supporting operation in the vacuum drying process.