The present invention provides a polishing composition with which it is possible to decrease a level difference to be unintentionally generated between dissimilar materials and a level difference to be unintentionally generated between coarse and dense portions of a pattern. The present invention relates to a polishing composition which contains abrasive grains having an average primary particle size of 5 to 50 nm, a level difference modifier containing a compound with a specific structure, having an aromatic ring and a sulfo group or a salt group thereof which is directly bonded to this aromatic ring, and a dispersing medium and of which the pH is less than 7.