The present utility model relates to a building structure, and in particular to a self-heat preservation building structure applied to extremely severe cold regions. The self-heat preservation building structure adopts a wood material, and comprises an independent foundation, a floor, a wallboard, a ceiling board and a roof board, wherein the independent foundation is disposed on a hard groundwork, and the upper end part of the independent foundation is provided with spigots for mounting wooden pillars; mortises are disposed in the lower ends of the wooden pillars and configured to mount longitudinal and transverse ground beams, and the upper ends of the wooden pillars are provided with criss-cross straight slots which are configured to mount longitudinal and transverse wooden beams; wooden square beams are mounted between the ground beams and between the wooden beams, and the wooden beams are provided with wooden braces; the floor and the ceiling board are respectively paved on the wooden square beams; the wallboard is spliced with the ground beams and the wooden beams in a mortise-tenon manner; the roof board is mounted on the wooden braces; and the wallboard is provided with a window opening for mounting a heat preservation window and a doorway for a wooden door. The self-heat preservation building structure has the following advantages: (1) the mortise-tenon structure is adopted, and (2) the original ecological environment of the extremely severe cold regions is protected.