The invention provides a fuzzy control method for a separation system during a cement grinding production process. The method comprises the following steps: S1, a variable membership function is built, and a fuzzy variable assignment table is acquired; S2, a fuzzy control rule is built, and fuzzy relation matrixes RRmp and Rv are acquired; and S3, according to a variable acquired instantly, a fuzzy control quantity is obtained through fuzzy calculation, and through a computer incremental control method, the cement grinding separation system is controlled. The fuzzy control method is adopted, the fuzzy relation between the rotation speed of the separator and specific surface area of milled cement and sieve residue and the fuzzy relation between a cold air valve and the specific surface area of the milled cement and the sieve residue are built, and a scientific and optimal separation process during the cement grinding production process can be realized.