Provided is a polishing composition including abrasive grains, a water-soluble polymer, and water. The water-soluble polymer includes a polymer (A) in which the adsorption ratio based on a predetermined adsorption ratio measurement is less than 5%, and a polymer (B) in which the adsorption ratio is 5% to less than 95%. Here, the polymer (B) is selected from polymers other than hydroxyethyl cellulose.