Demographic Analysis(DA) as well as Post Enumeration Survey(PES) are typical methods for evaluating completeness of census and vital statistics. In spite of its popularity, DA has never been attempted in Korea, while other international journals of demography have pointed out the backwardness of death registration in Korea in terms of DA approach. This paper introduces various DA methods and modifies them to be adequate for Korea census and vital statistics. Our method are also applied to reconstruct year-age-sex specific population and estimate their omission rates for year and age. Empirical analysis of census and vital statistics of Korea from 1985 to 2010 demonstrates high completeness of death registration in Korea, contrary to existing literatures. We also investigates abnormal patterns in census by comparing with reconstruction data in view of cohort, sex ratio and age ratio.