In many of his writings, the neo-confucianist Mou Zongsan (1909–1995) refers to Kant to support his own interpretation of Chinese philosophy. Among scholars, many of his views on Kantian concepts are controversially discussed. In this paper, I will analyse Mou's interpretation of the summum bonum, which is described by Kant as the harmony between happiness and virtue guaranteed by God. According to Mou, the summum bonum is the pinnacle of Western philosophy, comparable to the concept of Perfect Teaching in Chinese philosophy, but lost from the Occident since Kant. I will discuss Mou's three main interpretations of the possible relations between virtue and happiness. Then, I will present his main conclusion; the synthesis of the summum bonum with the doctrine of Perfect Teaching will form a universal approach to reviving the relation between virtue and happiness in both cultures.