The purpose of this study is studying the fantasy poems of Kim Goo-yong in 1950s. The poems of Kim Goo-yong composed in 1950s consistently have the issue of identity exploration. The poems 《Ideal of dream》, 《Flower of dissonance》 and 《Postmark》, which is the object of this study, clearly show the position of modernity held by the poems of Kim Goo-yong while focusing on the issues of identity, language and desire. This study focuses on following issues. First is the position of fantasy and reality in the poems of Kim Goo-yong. Prison is the starting point of my misconception while it is also the space, in which the principal agent immerses in fantasy deeper. My desire is completely exposed to the gaze of the other because the gaze of the other is the premise of a space in prison. In other words, the prison-setting is the condition for the appearance of fantasy. Second, the principal agent of 《Postmark》 is ‘erased principal agent’. He at last becomes a principal agent by answering to the demand of the symbolic; however, that principal agent creates the contradiction of principal agent being erased by having my demand not being won over to the demand of the other. ‘The woman with green coat’ in the gap between fantasy and reality is a being who insists without existing. In other words, she evokes a ‘living dead’ which survives indecorously. Third, the principal agent of this poem acknowledges the deficiency of self by denying the calling of the other. ‘I’ try to cognize the structure of misconception by faithfully fulfilling my desire while being separated from the symbolic. ‘I’ explore the possibility of going forward to new principal agent by way of ‘love’ on the other.