An antistatic film having an antistatic coating film on at least one surface of a polyester film, the antistatic coating film comprising a polymer having a polymerized unit represented by the following formula (1): ##STR00001## wherein R.sup.1 and R.sup.2 each independently represent a hydrogen atom or a methyl group, R.sup.3 represents an alkylene group having 2 to 10 carbon atoms, R.sup.4 and R.sup.5 each independently represent an alkyl group having 1 to 5 carbon atoms, R.sup.6 represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms or a hydroxyalkyl group having 2 to 10 carbon atoms, and Y.sup.- represents a halogen ion, a halogenated alkyl ion, a nitrate ion, a sulfate ion, an alkyl sulfate ion, a sulfonate ion or an alkyl sulfonate ion. The film is used in such applications requiring an antistatic property such as a protective film for a liquid crystal polarizing plate.