This article considers the ongoing debate over the role of competition law and constitutional law as well in protection of medium/small businesses in Korea. Recently the associations of medium/small firms have strongly argued that the Korean competition law should do something to protect medium/small businesses from big firms, and also the government should prohibit big firms from doing their businesses in the markets which are deemed suitable for medium/small firms. These arguments assume that bigness is evil, and smallness itself deserves special protection by the economic democracy clause in the Korean Constitution. Of course medium/small firms may pursue their own interests. However they do not have the right to sacrifice consumers and other firms’ welfare. Considering political influences of the associations of medium/small firms, politicians actually prepared the bills to protect them from the competition with big firms. However it should be noted that the purpose of the competition law is not to protect medium and small firms. Indeed the Korean competition law do not distinguish between medium/small firms and big firms. There is little doubt that the legislations designed to restraint competition among big firms and medium/small firms would impair big firms’ fundamental right to do business, distort market functions, and also reduce consumer welfare. Politicians must realize that ‘market competition’ itself has constitutional value, and economic democracy is nothing more than free market based on liberty democracy under the Constitution.