Abstract: Chora (χωρα), as the basis and premise of something, occupies a crucial status in the creative picture of cosmos. However, due to the text's ambiguity, there are multiple difficulties for understanding this conception. Mohr regards it as a mirror or medium, and calls the things in it an image, and then takes them as a mirror-image relationship. In contrast with Cornford, Mohr deepens the mirror analogy into the level of ontology. In his view, Plato's chora does not possess the function of bearing, but just exists as a function of reflection essentially, but Mohr's mirror analogyleads to the multiple difficulties for understanding Plato's chora. So this paper discussed and criticized Mohr's mirror analogy of Plato's chora, holding that it not only leads to the conflict with Timaeus, but also is paradoxical. Eventually, the analogy was reduced to a relational conception from the dimension of mutual basis between chora and elements' traces, the quality of relational chora was explored, and then the essential character of Plato's chora was interpreted.