Yoko Tawada is one of the few contemporary Japanese writers who writes in Japanese and German. She has transcended the limits of her native language and experienced, thought, translated, and written in the gap between languages. Based on the core concept of her poetics, "transformation," this paper explores the relationship between Tawada's translation and writing in order to reveal her motivation for writing, characteristics of literary language, and main creative ideas. “Transformation” runs through Tawada’s writing and translation process. Her writing is actually a kind of “transformed” translation, and her translation is also a kind of “transformed” writing. In the interactive relationship between the two, Tawada’s poetics of "transformation," as border poetics, presents the characteristics of cross-cultural and performance aesthetics.