Ex ante control mechanisms in the EU standardization process exhibit several shortcomings. For this reason, it seems necessary to establish whether the ex post judicial review of the process may compensate for these shortcomings. This article aims at identifying the possible gaps of judicial protection in the review of EU harmonized standards. To this end, the mechanisms of judicial supervision available in the EU legal system are reviewed in order to establish whether the current level of judicial control of the EU standardization process complies with the principle of effective judicial protection. The article first considers the possibility of a direct challenge against a European harmonized standard and subsequently the situation of an indirect challenge against a European harmonized standard through the preliminary ruling procedure. It concludes that the current system of judicial protection of the EU standardization process does not respect the principle of effective judicial protection.