The invention relates to a preparation method of calcium sulfoaluminate, a layered functional material. The preparation method comprises the following steps: (1) mixing a certain proportion of calcium sulfate, aluminum hydroxide and calcium oxide into a fully back-mixed explosive nucleation reactor , and add water higher than that of each material for mixing; (2) Use a fully back-mixed explosive nucleation reactor to synthesize sulfur under the conditions of a rotor speed of 4000-6000rpm, a voltage of 220-330V, and nucleation of 8-16min Calcium aluminate gel, then crystallize calcium sulfoaluminate gel at 90-150°C for 12-16h, cool down to 30-50°C, stir for 12-16h, then heat up to 90-150°C, cycle 3-5 times, can The layered functional material calcium sulfoaluminate is prepared. The advantage of the present invention is: the preparation method of the layered functional material calcium sulfoaluminate of the present invention, calcium sulfate, aluminum hydroxide and calcium oxide are nucleated and grown in a full back-mixing explosive nucleation reactor through a "one-pot method" , which effectively simplifies the preparation process of calcium sulfoaluminate, shortens the preparation time, simplifies the reaction operation, and improves the production efficiency.