The finance ministry's Enforcement Directorate is looking into whether Amazon's Indian subsidiary may have sold directly to customers but made it look as if the sales were made by other companies, the Journal cited two people familiar with the matter as saying.
India doesn't allow foreign firms to own majority stakes in retail companies that sell more than one brand.
Amazon is allowed there because it acts as a marketplace rather than a retailer, according to the Journal. Amazon was not immediately available for comment.