The invention discloses a dry tree semi-submersible platform with a self-mounting function. The dry tree semi-submersible platform with the self-mounting function comprises a platform hull; the platform hull comprises an upper deck, a lower buoyancy tank and a heave plate in sequence from top to bottom; the upper deck and the lower buoyancy tank are supported by four uprights; the uprights are fixedly connected to the lower buoyancy tank; the uprights can slide in the vertical direction of the upper deck; the tops of the uprights are fixedly connected with the upper deck; the lower buoyancy tank is connected with the heave plate through a mooring cable; and a ballast tank is arranged in the lower buoyancy tank. The dry tree semi-submersible platform with the self-mounting function has theadvantages that an upper module and a platform hull can be built on a shipyard or a slipway in an integrated manner without being mounted in a closed manner; after the building is finished, the overall gravity center of the platform is lower to be beneficial for dry towing transportation; as the heave plate is arranged at the bottom of the platform, the heaving motion performance can be improved to realize dry tree oil extraction; the mooring cable tie-back operation can be finished by using a platform crane, and the pretension force of the mooring cable is produced by deadweight of the heaveplate, and the platform does not need a windlass.