The impact of International Large-Scale Assessments (ILSAs) is growing day by day around the world. Of these, the Programme for International Student Assessment (PISA) is particularly influential globally including in South Korea. Although the authority of PISA as a soft power is widespread and affects many countries, individual countries are not unconditionally affected but can consider and adopt PISA results according to their own logic and interests. This is the starting point for this thesis which focuses on South Korea. Of many local actors in South Korea, two leading newspapers were selected for analysis. From the perspective of externalization thesis, this thesis examines how the newspapers have utilized the PISA results in the debate on education in South Korea. This was done by comparing articles related to PISA published in two prominent newspapers of different political inclination since the first PISA cycle in 2000 and until the year of 2018 - the last time period that can be examined in full within the time limits of this thesis. The study shows that there is an important educational discourse in the two newspapers using the PISA results. The key topics are: University entrance-oriented education, high school equalization policy, excellence in education, efforts to reduce academic burden, and national assessment of educational achievement. There is a close relationship between the key issues discussed in the newspapers and those of the different governments during the period of analysis. Furthermore, with the exception of the university entrance-oriented education issue, the newspapers have different views on the predominant issues reflecting their respective political inclination. Their contrasting positions were advocated for using different parts of the PISA results, but focused on the same aspects in the process of forming public opinion, namely 1) by discussing South Korean PISA performance; and 2) by comparing to the performance and practice of other countries.