Energy is the motive power of economical growth. Thus, every country has struggled historically to secure the energy source and develope the technology to use effectively. In Korea who has not sufficient natural resources, nuclear energy is the most favorable power for the electricity in the strategical and environmental views. Korea has recognized the importance of nuclear technology development in 1950s and built 2 reactors in 1962 and 1972. The first commercial power plant started the operation in 1978, and currently 14 units are being operated or under construction with generating about 50% of total electricity. moreover a masterplan has been established in 1992 to build more 13 plants until 2006. Previous efforts for development of the self-sustained technology have been focused on the construction of nuclear power plants in two major fields of reactor design and nuclear fuel manufacture. However, the results are not satisfactory in the basic design and whole fuel cycle technology even some of success has been achieved in the detail design and nuclear fuel self-production. The reasons put on weak investment of basic technology development, impetuous construction, and absence of continuous performance of national long-term plan. Recently, the "Declaration on Nuclear-free Korean Peninsula" interrupts even researches of spent fuel reprocessing which is useful for nuclear waste reduction and maximizing uranium use. Thus, in order to overcome such weaknesses in technology independence and build the next generation reactor which would remarkably increase the safety, the government and KEPCO established a long-term plan for technology development in 1992 which is divided to three major parts; next generation reactor development, advanced fuel technology development and radiowaste management technology development. Finally, it would be strongly recommended that in order to succeed this plan the close cooperation between nuclear industries, research institutes and universties as well as continuous support of government is required.