An integrative deep draft floating production platform with unconditional stability and an offshore installation method thereof are disclosed. The platform comprises an ring
ballast tank (1) at the bottom, some columns with small cross sections (2), an ring
buoyancy tank (3) at the middle part, some columns with large cross sections (4), and an upper drilling rig and oil gas
processing module (5). The
ballast tank adopts a permanently fixed
ballast, and the tank is internally filled with weights to ensure that the center of
buoyancy of the platform is higher than the center of gravity. The columns with large and small cross sections are uniformly arranged on the
buoyancy tank and the
ballast tank respectively, and the lower parts thereof are respectively integrated with the buoyancy tank and the
ballast tank. Each column with a large cross section is provided with a central pore canal (7) axially, a lower part in the central pore canal is provided with a chopping board connection structure (8) with a groove. After the construction is completed, the columns with small cross sections are inserted into and pass through the central pore canals of the columns with large cross sections correspondingly, and the platform is in a folded state. Each column with a large cross section is provided with a group of
mooring lines (15). The drilling rig and oil gas
processing module is installed in the construction site, and the platform is transported to the installation site by a dry tow or wet tow as a whole and then is installed. The platform can be applied to deepwater oil and gas exploitation under harsh marine environment.