This study discussed the principles of the operation of imagination in ading plays in order to propose ways to educate students to read plays in the light of the genre-specific features. Reading plays need two sort of imaginations, the imagination as reading literature and performative imagination as the staging of plays. These imaginations are maximized in the course of directing a play. This study analyzed the directing notes a director writes for a performance after reading a play to examine how imagination works. Upon investigation, the structure of the operation of imagination, including `the display of the written world through imagination of awareness,` `the critical investigation of the revealed world through imagination of world ordering,` `the stylization of criticized world through imagination of world making,` and `the staging of the stylized world through imagination of representation` in reading plays was identified by discussing imagination and investigating theatricality in literature education. And the aspects of the operation of imagination were examined from Yoon-taek Lee`s directing notes for Kwang-rim Kim`s Hong-DongJi Is Alive in which the director`s imagination is revealed. The present study is significant in that it contributed to reading plays in the light of the genre-specific features by identifying the structure of how imagination operates in reading plays.