Now we have faced to two fundamental population problems: The one is over-population problem in proportion to the nation's total area, 99,434 $km^2$, and the other is unbalanced population distributions in the provincial districts of administration (16th local governments). For example, the population density of Seoul city is 16,335 persons, and the nations population density of South Korea is 464 persons for 1 km$^2$. At the first part of this study, we introduced the origins and historical back grounds of Formal Demorgraphy. And the second part, we suggest some useful indicators of urbanization of rural populations in terms of Gini's Coefficients of Concentration. As the result, we can show that the ecological Gini's Coefficients of Concentration, during the periods covered by this study, have been increasing extraordinary: 0.349, 0.433, 0.532, 0.581, 0.633 and 0.626 in 1970, 1980, 1985, 1990, 1995, 2000 A.D. respectively. However, the trend of urbanization (concentration of population) of Korean population has been the relative equilibrium state of 0.63 from 1995 to 2000 A.D.