Synesthetic metaphor is an important research topic in recent years. Yet, there is almost no discussion on the underlying motivation for the occurrence of synesthetic metaphor. Embodied cognition theory (EC) views that cognition is shaped by the kind of body possessing the organisms. According to EC, people can conceptualize things based on bodily experience, where the more abstract and less direct experience is understood by means of the concrete and more direct experience. In order to address the gap, this paper tends to choose gustatory adjective “suan (酸/sour)”, one of the gustatory experience, which is also extensively used to express people’s feeling and life experiences in Chinese, to further study the motivation that stimulates the synesthetic mapping from the gustatory domain to another sensory domains.