Objective: Although Trans sexuality and sex change might be considered as a personal issue, it has some influentional socio-cultural causes and consequences. This article aims at the illustration of Trans sexuality in Iran. To achieve this goal, the theoretical studies have been applied to describe the nature of Trans sexuality. Later sex transition and legal system in Iran will be explained. And finally some social and cultural consequences of Trans sexuality will be discussed. Method: This study has been carried out by a survey including interviews with two different samples groups: 1) the Trans sexuality policy makers, 2) forty cases of transsexuals. Findings and Results: The findings show while Iranian legal system is not against trans sexuality and sex transition, transsexuals suffering from gender identity disorders are encountered some social and cultural problems in their private lives and public sphere