This study aimed at analyzing the keywords and authors of the KCI listed theological journals and finding the official research performance of Korean theology. This study divided the periods in two according to how duplicate the authors are and found hierarchical clusters by analyzing 92 keywords using the McQuitty method. In analyzing them, the Ward linkage method was selected to prevent the authors from gathering into a small number of clusters. Also, to find how influential the journals were to the keywords, the keywords and the percentage of the journals in them were presented together. The authors were analyzed in terms of deciding the positions of them using normalized performance index representing the number of journals and growth index as a growth tendency. Especially, significant researchers were all reformed theologians in a growth index. In the analysis of the keywords of the KCI journals and the authors, the main subject terms of the Korean theology were related to systematic theology and the New Testament. By analyzing the KCI listed journals as the Korean official citation index, this study has made a difference to the advanced articles analyzing the non-KCI listed theological journals.