The doctrine of the imago Dei was by no means a central issue in Karl Barth's early thought. It had accidentally become the spotlight since his dispute with Emil Brunner regarding the legitimacy of natural theology in 1934. The viewpoints emerged from the dispute finally formed his theological anthropology. In discussing Barth's understanding and interpretation of the imago Dei, the present article is divided into four parts. The first three parts deal with the relationship between the imago and "Jesus Christ", "humanity", "covenant" respectively, and the fourth is a critical evaluation of a highly controversial bioethical issue, i.e. "cloning human being", according the conclusion made by the preceding parts.