Upcoming 21st century, Management circumstance for a small and medium enterprise have been rapidly changed by Knowledge management, Informationization, Hi-technology. Changing from an era of small concept to strong concept, It will be a severe innovation period and can not survive with life as the same as the past, It is the era of best which mean only the best can survive, None of the average faculty can survive. Due to rapid proceeding of innovation of Informationization, It stimulate acceleration of technology innovation, infinity competition regardless the nation boarder, result in proceeding to Informationization. A small and medium enterprise is defined as smaller size of business than big business as point of capital, employee, output. It is concept, which usually used against concept of big business. When define a small and medium enterprise, criteria to determine a small and medium enterprise is depends on country and a category of business. However, In every country, A small and medium enterprise is getting be bigger and importance factor in whole industry. A small and medium enterprise is well developed and also well balanced with a large enterprise in the developed country. All around in the world, Interest about a small and medium enterprise is becoming higher. It is actively researching into a small and medium enterprise as the mean to create new employment, new industry, as means to from integration of a all and medium enterprise,as source of high competitive power. The status quo of rapid changing into informationization have been realized at considerable level in Korea. Information society is defined as information technology is main key to determine individuals competitiveness, which can solve effectively the side effect result from industrialization. It cleary imply that information technology is the most promising and important industry in 21st century. Therefore, We should seek to foster independent a small and medium enterprise and develop them corresponding to new concept of a small and medium enterprise in 21st century. The main frame of policy should be new economic system, which can contribute establishment of a small and medium enterprise, management innovation. It also attribute a small and medium enterprise to reveal their creative. New economic paradigm in 21st will be expanded with organization, market, technology. So far, a small and medium enterprise has been acknowledge as economic weaker and the one should be protected. However, In 21st century a small and medium enterprise will be considered as active majority or a source of creative. Development of technology to produce a small quantity with variety product and acceleration of knowledge and informationization will result in comparative merits of a small and medium enterprise. Hereby, The role and relative importance of a small and medium enterprise in our economic will getting be larger and It will be developed as the main force to activate the economic. However, Only a small and medium enterprise, which overcome difficulty with active desire and effort to improve their lot can be developed as a competitive enterprise in 21st century in considering themselves to be developed as diversity, active, independent, business by an enterprise.