The invention discloses a preparation method for improving the ring pressure strength of a low-gram-weight T paper board, and the preparation method comprises the following four steps: (1) selecting raw materials, namely taking corrugated paper and offset printing periodical paper as raw materials; (2) preparing slurry, to be more specific, mixing the two raw materials obtained in the step (1) according to a ratio, carrying out crushing, impurity removal, fiber grading, heat dispersion and concentration treatment, and respectively storing long fiber slurry and short fiber slurry in respectiveslurry pools for later use; (3) preparing pulp, to be more specific, preparing surface layer pulp and bottom-layer pulp according to the proportions from the long fiber slurry and the short fiber slurry obtained in the step (2); and (4) making the T paper board, to be more specific, respectively allowing the surface layer pulp and the bottom-layer pulp obtained in the step (3) to pass through a fan pump and a pressure screen, then be conveyed to a surface layer and bottom layer pulp box pulp feeding total pipe for being loaded onto a net for forming, then enter a pressing part, a front and a rear drying part, surface sizing, a calender and the like for treatment after vacuum dewatering by a net part, and enter a winding machine, a rewinding machine and a packaging machine to obtain the low-gram-weight T paper board.