To obtain the subject composition excellent in stability after curing and useful for automotive parts, etc., without having problem on dispensability of vulcanization accelerator by adding a salt from a specific organic base in the form of a master batch having a specific composition to a fluorine rubber, etc.

In this method for producing a fluorine rubber composition comprising (A) 100 pts.wt. fluorine rubber, (B) 0.1-10 pts.wt. salt deriveed from an organic quaternary ammonium hydrogensulfate or from 1,8- diazabicyclo[5.4.0]-7-undercene, (C) 0.5-30 pts.wt. metal (hydr)oxide, (D) 0.5-20 pts.wt. organic peroxide, (E) 0.5-20 pts.wt. polyfunctional compound and (F) 0.1-20 pts.wt. polyhydroxy compound or phenolic compound, the component B is added in the form of master batch in which 1 pt.wt. component B is previously mixed with 0.3-5 pts.wt. of a polar solvent (B1), 0.5-10 pts.wt. of a natural or synthetic silicate (B2) having ≥100cc/100g linseed oil absorption amount and 2-10 pts.wt. component A.