The objective of the present invention is to provide a contact lens solution that is safer to eyes such that it has little or no effects on eye tissue and has the versatility that makes the solution applicable to a wide range of contact lenses, while exhibiting desirable anti-Acanthamoeba activity. The objective is achieved by the anti-Acanthamoeba contact lens solution containing a cationic polymer having an average molecular weight in a range of 150,000 to 1,600,000 and having in its molecule a diallyldimethylammonium chloride unit and an inorganic salt.