The purpose of this study is to trace the diachronic dynamics of conceptual definition of the terms related North Korean social welfare by approaching with historical narrative method. In this study, the terms to be analyzed are 'social security' and 'social security system' etc. For this purpose, this study used the official dictionary of North Korea as an analyzer. Accordingly, this study was followed up chronologically with period division through the literature search based on the dictionary of North Korea. As a result of the analysis, the dynamics of North Korean social security system can be divided based on 1985 with tracing focusing on coverage, benefits, finances, and delivery system. The major features are as follows: First, from this year, the grace and consideration of Kim Il Sung and Kim Jong Il were both emphasized. Second, in this period, North Korea shows specific statements of universalism of the coverage and kinds of benefits. Third, finances were almost the same as those of the 1970s. Fourth, the delivery system did not have a separate reference except for protection of the facility at all times. Fifth, direct benefits related to unemployment protection were absent throughout the period. On the other hand, with a content-oriented approach, North Korea showed progressive development until 1985 over the passage of time and then stagnated. Also, North Korea, looking at the specifics of explanations and statements in response to the passage of time, showed passive statements of the 1950s developed into active statements. However, from 1985 until 2002, there is no substantial change in content. In addition, the universality of the socialist system and the speciality of the North Korean regime appeared simultaneously in the process. The universality of the socialist system is represented by the universalism of the coverage and the preference of the people of national merits. In case of specialty, North Korea emphasized the sincerity of Kim Il Sung and Kim Jong Il as rulers for 'social security' and 'social security system'.