Disclosed is a surface treating agent containing fluorine-containing polymer having: (A) a repeating unit derived from a fluorine-containing compound which is represented by the following formula: CH.sub.2.dbd.C(--X)--C(.dbd.O)--Y--[--(CH.sub.2).sub.m-Z-].sub.p--(CH.sub- .2).sub.n-Rf (I) (wherein X is a hydrogen atom or a methyl group), (B) a repeating unit derived from a monomer containing no fluorine atom, if necessary and (C) a repeating unit derived from a crosslinkable monomer, if necessary. This surface treating agent has excellent water repellency, oil repellency and antifouling property.