The invention relates to the technical field of toilet bowl production, in particular to a toilet bowl seat ring and a split type formation method thereof. The split type formation method of the toilet bowl seat ring comprises the steps that firstly, the prototype of the seat ring and the prototype of a water inlet are manufactured first of all, high pressure molds, which are two open molds, are manufactured by means of the two prototypes, slurry is poured into the high-pressure molds, the slurry is hardened, then a seat ring mud blank and a water inlet mud blank which are mutually independentare obtained at the same time, a water hole and a seat hole are drilled on the seat ring mud blank, and then the two mud blanks are stuck together to obtain the toilet bowl seat ring. By the adoptionof the split type formation method, the mold structure is simple, mold making is easy, workers can conveniently conduct operation, the labor intensity is low, and the production efficiency is high.