The purpose of this study was to explore the development of a 21-years-old transgender's gender identity and the support systems he received. We collected data through semi-structural interviews. Based on Devor's Identity Formation Model, the data were analyzed using the category-content analytic technique. The results of this study found that the transgender experienced the oppression by patriarchy and heterosexism within the LGBT groups and in intimate relationships. Moreover, he was confronted with the military service, medical, and diagnostic issues by the current laws and government policies. In the development of his gender identity, he felt isolated due to others' lack of understanding about transgender. However, the transgender has taken life bravely even though he was misunderstood by his families and others and received few supports.