This paper aims to show changes in the discourse on welfare(bokji) in Korean newspapers. For analysis, a modern diachronic corpus was built by collecting newspaper articles covering the periods of five presidential elections. By analysing clusters and concordance lines generated from the corpus, the discoursal changes on welfare(bokji) are detected. Firstly, the welfare discourse changed from selective welfare to universal welfare. Secondly, the term "free" welfare is found to be used with negative semantic prosody. Thirdly, conservative candidates pledged welfare without tex increase, while the voters thought it was untrustworthy. Fourthly, a social consensus on welfare expansion and the increase of welfare budget is formed, but the issue of how to raise the funds has become controversial. Lastly, discussion on a welfare state starts in earnest.