The concept of corporate citizenship has been developed as one of the core values of corporate social responsibility activities of firms who pursue sustainable management. This study shows an example of corporate citizenship activities by introducing POSCO’s case which is representative for Korean firms. We adopt a model of Mirvis and Googins(2006), which suggests dimensions and stages of corporate citizenship activities, to evaluate POSCO’s current status and find future directions. Using Corporate Citizenship Management Standards(CCMS) Handbook that POSCO made in 2020, we find that among POSCO’s 40 activities categorized in terms of business, society and people, 13 activities can be viewed as elementary and engaged stages which are lower levels, 13 activities as an innovative stage which is the middle level, and 14 activities as integrated and transforming stages which are upper levels. The results show that these activities spread evenly throughout all levels. Specifically, while activities in the category of business spread widely in all stages including the transforming stage as the highest level, those in the category of society are concentrated in engaged, innovative and integrated stages, and those in the category of people are in the innovative stage only. We suggest that POSCO’s rapid advances into upper levels of corporate citizenship activities in just two years should be attributed to strong leadership of top management. The result of this study implies that success of corporate citizenship activities seems to depend on top-down leadership as well as bottom-up initiatives.